- Keith David - Captain Ira Merit
- Kelly McGillis - Nicole Whitley
- Ron Rifkin - Dr. Martin Nodel
- Jeremy Sisto - Tom
- Jon Tenney - Aidan Hunter
- Eric McCormack - John Virgil
- Doug Savant - Kel
- David Ogden Stiers - Reverend Dr. Thomas Tilford
- Rachel Ticotin - Theodora 'Teddi' Madden
- Casper Van Dien - Jake Miller
- Sherilyn Fenn - Nora Griffiths / Nora's Clone
- Michael Buie - Private John Stanhope
- Colin Cunningham - Professor George Ernst
- Kandyse McClure - Brianna Lake
- David Palffy - Kramer
- Robert Clothier - Dr. Linstrop
- Ralph Waite - Gene Morton
- Gregory Smith - Young Paul
- Lloyd Bridges - Col. Kress
- Howie Mandel - Karl Durand
- Don Franklin - Tim McAllister
- Mark Hamill - Dr. Sam Stein
- Colin Ferguson - David
- Jessica Tuck - Linda Andrews
- Malcolm McDowell - Ship (voice)
- Timothy Busfield - Dr. Jon Holland
- Richard Thomas - Dr. Stephen Ledbetter
- Colin Mochrie - Dale La Rose
- Adam Hann-Byrd - Kevin Buchanan
- Jane Adams - Mona Bailey
- Nathan Fillion - Michael Ryan
- Matt Craven - Alan Wells
- Harley Jane Kozak - Prisoner No. 98843
- Dylan Walsh - Sgt. Eldritch
- Joely Fisher - Amy
- Gordon Clapp - Dr. Randall Strong
- Alan Ruck - Howard Sharp
- Dennis Haysbert - Joshua Finch
- Mykelti Williamson - Dr. Michael Alders
- Chris Sarandon - Dr. Pallas
- Alan Rachins - Maculhaney
- Wil Wheaton - Cadet
- Katharine Isabelle - Tammy Sinclair
- Robert Sean Leonard - Robby Archer
- Kevin Nealon - Dr. Mark Crest
- Perry King - Senator Richard Adams
- Jon Cryer - Trevor McPhee
- David McCallum - Joshua Hayward
- Joanna Gleason - Leslie
- Shawn Ashmore - Morris Shotwell
- Chris Elliott - Jack Parson
- Barry Corbin - Carlton Powers
- Kirsten Dunst - Joyce Taylor
- David Hyde Pierce - Dr. Jack Henson
- Daphne Zuniga - Juliette Kagan
- Ron Perlman - Lt. Col. Brandon Grace
- George Newbern - Ryan Unger
- Jasmine Guy - Captain Teri Washington
- Enrico Colantoni - Michael Burr
- Steven Weber - 8x10 Man
- Dana Ashbrook - Cain
- Zack Ward - Link
- Frances Fisher - Lady Julia
- Frances Sternhagen - Jean Anderson
- Peter Onorati - Frank Martin
- Stephen Lang - Dr. James Houghton
- Yee Jee Tso - Hong
- Mario Van Peebles - Captain William Clark
- Clint Howard - Dennis
- Robert Hays - Dr. Peter Halstead
- Marlee Matlin - Jennifer Winter
- Daniel Benzali - Graham Highfield
- Tom Arnold - Jerry Miller
- Marcia Cross - Katherine Woods
- Robert Picardo - Emmet Harley
- Michael O'Keefe - Eddie Wexler
- Diana Scarwid - Elizabeth Halsey
- Holly Dignard - Cindy
- Kim Hawthorne - Morgan Winters
- Cicely Tyson - Justice Gretchen Parkhurst
- Robert Patrick - Major John Skokes
- Jason Gedrick - Captain Kelvin Parkhurst
- Mimi Kuzyk - Dr. Leslie McKenna
- Michael Dorn - Pete Claridge
- Megan Follows - Karen Ross
- Jan Rubeš - Robert Greene / Older Karl Rademacher
- David Hemblen - Commandant
- Dean McDermott - Ray Carter
- Matt Frewer - Norman Glass
- Leland Orser - Dr. Arthur Zeller
- Daniel J. Travanti - Chairman Thornwell
- Helen Shaver - Cathy Kress
- Howard Hesseman - Dr. Emory Taylor
- Angeline Ball - Cass Trenton
- Barbara Williams - Caitlin Doyle
- John Diehl - Joe
- Tim Progosh - Walter Black
- Alan Thicke - Donald Rivers
- Natasha Henstridge - Emma
- Peter Williams - Chili Wayne
- Bill Smitrovich - Lt. Joseph Dane
- M. Emmet Walsh - Sanford Vallé
- Debrah Farentino - Dr. Rachel Carter
- Ronny Cox - Lt. Col. Lester Glade
- Bruce Davison - Dr. 'Mac' McEnerney
- Kenneth Welsh - Dr. Vasquez
- Alexander Pollock - Boy
- Bob Gunton - Clute Nichols
- Lisa Zane - Natalie Grainger
- Cary Elwes - Dr. John 'Jack' Percy Vilmorin York
- Elizabeth Peña - Dr. Jennifer Martinez
- Sandrine Holt - Jade / Laura
- Stephen McHattie - Dr. Sherrick
- Robert Foxworth - President Charles Halsey
- Jeffrey Jones - Dr. Scott Perkins
- Michael Gross - Professor Stanley Hurst
- Michelle Forbes - F.B.I. Agent Jamie Pratt
- Xander Berkeley - Terry McCammon
- Clancy Brown - Sergeant Linden Styles
- Ally Sheedy - Carter Jones
- Mackenzie Astin - Patrick Tarloff
- Judd Nelson - Harry Longworth
- Allison Hossack - Erin Whitley
- Tygh Runyan - James Scardale
- Heather Graham - Alicia
- Mackenzie Phillips - Boo Weston
- William McNamara - Kimble
- Rae Dawn Chong - Karen Heatherton
- Patrick McKenna - Dr. Seigel
- Daniella Evangelista - Cindy Parker
- Chris William Martin - Gavin
- Christine Elise - Lieutenant Rosen
- Megan Leitch - Barb
- Leonard Nimoy - Thurman Cutler
- Alberta Watson - Lynda Tillman
- Costas Mandylor - Lee Taylor
- Larry Drake - Robert Vitale
- Chad Willett - Lt. Christopher Lindy
- Harold Gould - Gerry
- Meghan Ory - Danielle Hobson
- Robert Duncan McNeill - Commander Ellis Ward
- Max Martini - Curtis Sandoval
- Gordon Pinsent - Dr. Steven Molstad
- Alyssa Milano - Hannah Valesic
- David Fredericks - Sheriff Lewis
- Michael Rooker - Colonel Beckett
- Jack Noseworthy - Man
- Chris Eigeman - Caleb Vance
- Tara Spencer-Nairn - Heather
- Wallace Langham - Ezekiel / Daniel Faraday
- Jayne Heitmeyer - Barbara
- Jessica Lundy - Theresa McPhee
- Brent Spiner - Professor Trent Davis
- Colm Feore - Major Mackie
- Sonja Smits - Dr. Anne Crain
- Margot Kidder - Serena
- Barbara Garrick - Dr. Ellen Kersaw
- Jessica Amlee - Young Lorelle
- Amanda Plummer - Dr. Theresa Givens
- Noel Fisher - Brae
- Richard Yearwood - Lawrence
- Joe Pantoliano - Stan Harbinger
- Sheena Easton - Melissa McCammon
- Gary Basaraba - Ben Miller
- Guylaine St-Onge - Dr. Helene Dufour
- Nora Dunn - Laura Sinclair
- Marilyn Norry - Flo
- Cynthia Preston - Mina Link
- Jamie Luner - Dr. Candace Maguire
- Cindy Girling - Saleswoman
- Dwight Schultz - Leviticus Mitchell
- Beau Bridges - Dr. Simon Kress
- Michael Hogan - Dr. Lawrence Sinclair
- French Tickner - Father Puglia
- Peter Breck - Kendal's Father
- Dale Midkiff - Tom Cooper
- Christopher Shyer - Harold Zimmer
- Charlene Fernetz - Corinne Virgil
- Mel Harris - Dr. Christina Markham
- Sara Botsford - Dr. Gail Cowlings
- Beau Starr - Jack, the Detective
- Callum Keith Rennie - Carlito
- Gary Cole - Detective Ray Venable
- Brad Johnson - Captain Sam Abbott
- Jay O. Sanders - Ed Barkley
- Graham Greene - Chief Weapons Officer
- Kerr Smith - Zach Burnham
- Tom Irwin - Dr. Ian Michaels
- C. Ernst Harth - Silverface
- Terri Hawkes - Dr. Cleo Lazar
- Wendel Meldrum - Renee Stuyvescent
- Finn Carter - Courtney Bowe
- D.W. Moffett - James Heatherton
- Sam Robards - Ben Kohler
- Lela Rochon - Beth Carter
- Sean Patrick Flanery - Eric Waters
- Ralph Macchio - Dr. Neal Eberhardt
- Jenny Cooper - Laura White
- Torri Higginson - Alyssa Selwyn
- Bruce French - Wayne Fowler
- John Heard - Paul Stein
- Kim Cattrall - Rebecca Highfield
- Kyle Labine - Joe
- Andrew Younghusband - D.J.
- Zachery Ty Bryan - Ray
- Laura Leighton - Anne Marie Reynolds / Marie Reynolds
- Roman Danylo - Young Leon Zgierski
- Joshua Leonard - Andy Larouche
- Rebecca Jenkins - Dr. Louise Burrows
- Mackenzie Gray - Martin Reese
- Amanda Tapping - Cmdr. Kate Girard
- Christianne Hirt - Sheila Morrison
- France Nuyen - Madame Li Yu
- Peri Gilpin - Dr. Rebecca Warfield
- Sandra Nelson - Leslie Travers
- Aaron Douglas - Kevin Lockwood
- Neil Patrick Harris - Howie Morrison
- Roddy Piper - Marlon
- Josh Brolin - Jack Pierce
- Catherine O'Hara - Becka Paulson
- P.J. Prinsloo - Eric
- Andrea Roth - Dr. Dana Elwin
- Brad Loree - Patrol Android
- Chris Potter - Captain Turner
- Jennifer Rubin - Rose Ciotti
- Esai Morales - Frank Kelton
- Louis Del Grande - Detective Renfro
- Michelle Johnson - Ady Sutton
- Kirby Morrow - Kirby
- Polly Shannon - Human Operator of Starfighter-88
- James Le Gros - Ben Conklin
- Darryl Quon - Asian Worker
- Daniel Baldwin - Dan Kagan
- Samantha Mathis - Marie Wells
- Lawrence Dane - General Covington
- Jennifer Beals - Robin Dysart
- Peter Wingfield - Dwight Bordon
- Vanessa Morley - Miranda
- Megan Gallagher - Detective Terry Russo
- Joshua Jackson - Devon Taylor
- C. Thomas Howell - Capt. Miles Davidow
- Brad Rowe - Daniel
- Gary Busey - Ezra Burnham
- Tabitha St. Germain - Delia Pendergast
- Eugene Byrd - Ronnie Dell
- Bonnie Bedelia - Nancy McDonald
- Rachael Crawford - Sherry McAllister
- Burt Young - Captain Parker
- Alex Zahara - Karl Rademacher
- Jason Priestley - Anthony Szigetti
- Michele Greene - Joan Garrison
- Cynthia Geary - Teryl Bouton
- William Hickey - Harlan Hawkes
- Janyse Jaud - Woman on Suicide Helpline
- Benita Ha - Cute Lab Technician
- Richard Ian Cox - Mark McPhee
- Barry Pepper - Tyson Ruddick
- Jason London - Jay Patton
- Andrea Martin - Lil Vaughn
- Gary Jones - TV Host
- Gary Jones - Duncan
- Charlton Heston - Chief Justice Haden Wainwright
- Annette O'Toole - Commander Lydia Manning
- Fred Savage - Danny Martin
- Robert Wisden - Justin Wells
- Robert Wisden - Sam Winter
- Glynis Davies - Dr. Baker
- Jody Racicot - Oren Edgar
- Julian Christopher - David Aftergood
- Robin Mossley - Doctor
- Carla Boudreau - Actress
- Merrilyn Gann - Gwen Wellington
- Nicholas Campbell - Frank Daniels
- Kaj-Erik Eriksen - Josh Dayton
- Roger Barnes - Tyler
- Frank Ferrucci - Receptionist
- Molly Ringwald - Allison Channing
- Paul Popowich - Tom Palmer
- Rebecca Toolan - Mrs. Whelan
- Cliff Robertson - Theodore Harris
- Daniel Hugh Kelly - Alex Buchanan
- Bob Morrisey - Dr. Benton Adler
- Nicole Eggert - Sarah Burnham
- Rebecca De Mornay - Woman
- Shane Meier - Mark
- Shane Meier - Young Kevin
- Ken Kirzinger - Moloch
- Natsuko Ohama - Dr. Stephanie Codada
- Jed Rees - J.D. Kelton
- María Conchita Alonso - Marie Alexander
- John Wesley Shipp - Coach Peter Shotwell
- Dina Meyer - Dr. Rachel Harris
- Peter Donat - Principal Kern
- Michael Moriarty - Solicitor-General Wallace Gannon
- Colin Foo - Mr. Chow
- Christine Willes - Nurse Yvette
- Erin Daniels - Barbara Chafey
- Rod Wilson - D.J.
- Scott Vickaryous - Young Sinclair
- Dave 'Squatch' Ward - Giant Convict
- Page Fletcher - Joe Travers
- Christine Lippa - Nurse Hendricks
- Lindsay Crouse - Gwen Sawyer
- Robert Ito - Colonel Raymond
- John Spencer - Col. Wallis Thurman
- Jan D'Arcy - Senator Sara Watson
- Jan D'Arcy - Martha Adams
- Ryan Phillippe - Russell 'Rusty' Dobson
- Silvio Pollio - Anthony
- Mig Macario - Lab Tech
- Swoosie Kurtz - Justice Kendall Woods
- Freda Perry - Nurse
- Dey Young - Carol Martin
- Kendall Cross - Allison Morris
- Kelly Rowan - Isabelle Pierce
- Kelly Rowan - Kristin
- Louis Chirillo - Cheech
- Rachel Cronin - GRS Girl - Melanie
- John Savage - Lucas
- Michael Dolan - Rob Anderson
- Victoria Morsell - Candace
- Peter Boretski - Leon Zgierski
- Dean Barrett - Stephen
- Thora Birch - Aggie Travers
- Hal Holbrook - Justice Oliver Harbison
- Donnelly Rhodes - Senator
- Donnelly Rhodes - General James Eiger
- John Maclaren - Rosen
- Tony Alcantar - Director
- Diana Stevan - Ruth
- Sofia Shinas - Mary 25
- Sofia Shinas - Valerie
- Robert Loggia - Justice Earl Clayton
- Steve Makaj - Officer Brown
- Tracy Waterhouse - Debra
- Kevin Conway - Mr. Portis
- Sam Vincent - Akira Matsumoto
- Sam Vincent - Jerome Horowitz
- David-Paul Grove - Polk
- Colleen Wheeler - Uma
- Richard Side - Ike Pilchard
- Holly Ferguson - Heather
- Holly Ferguson - Miriam Zgierski
- Peter Stebbings - Luke
- Peter Stebbings - Seth Todtman
- Anthony Harrison - Detective Saunders
- Yvonne Campeau - Jaru
- Yvonne Campeau - Nurse Thomas
- Ted Kozma - Mangled Man
- Fawnia Mondey - New Human
- Stevie Vallance - Sandra
- Russell Porter - Actor
- Brian Arnold - Newscaster
- Ron White - George Nichols
- Sebastian Spence - Young Gerry
- Bruce Boxleitner - Senator Wyndom Brody
- Kathryn Anderson - Woman
- J. Douglas Stewart - Watts
- Sarah-Jane Redmond - Kendal's Girlfriend
- Sarah-Jane Redmond - Kelly Risely
- Sheila Larken - Francis Hunter
- Mitchell Kosterman - Police Officer
- Mitchell Kosterman - FBI Agent
- Claire Rankin - Kyra
- Claire Rankin - Ariel
- Nicole de Boer - Cadet 2nd Class Bree Tristan
- Nicole de Boer - Rachel Sanders
- Karen Elizabeth Austin - Old Woman
- Corrie Clark - Young Sylvia
- Corrie Clark - Young Theresa Givens
- Jesse Moss - Sean Tenzer
- Jesse Moss - Jason Stewart
- Jesse Moss - Jason
- Rachael Leigh Cook - Cassie Boussard
- Peter Flemming - Tom Young
- Jonathon Young - Billy
- Jonathon Young - Young Man
- Fred Henderson - Acosta
- Fred Henderson - John
- Lane Smith - Dr. Malcolm Boussard
- Brad Swaile - Louis Boussard
- Shannon Beaty - Young Cassie
- William Sadler - Frank Hellner
- Nancy Allen - Rachel Rose
- Charles Martin Smith - Spencer Deighton
- George Touliatos - Darrow
- Alan Scarfe - Dr. Royce
- Alan Scarfe - Montgomery Bennett
- Martin Kemp - Michael Deighton
- Deryl Hayes - Policeman
- Mark Saunders - Lab Assistant
- Richard Grove - Kadimas
- Nicholas Lea - Jacob Hardy
- Nicholas Lea - Mac 27
- Kent Gallie - Jeffrey Littman
- Madison Graie - Nancy
- Garry Chalk - Detective Barnett
- Garry Chalk - Detective Frank Dayton
- Garry Chalk - General Seawell
- Ryan Reynolds - Paul Nodel
- Ryan Reynolds - Derek Tillman
- Jason Griffith - Medical Technician
- Codie Lucas Wilbee - Clark Howell
- Stephen Shellen - Wayne Haas
- Phillip MacKenzie - Detective Dofner
- Tom McBeath - Dr. Joseph Mitchell
- Tom McBeath - Detective Roth
- Michael Sarrazin - Marty Kilgore
- Michael Sarrazin - Stranger
- Kymberly Sheppard - Victorine Demon
- Kymberly Sheppard - Woman in Bath
- Paul Raskin - Morgue Attendant
- Terry Arrowsmith - Fletcher Demon
- Garry Davey - Randall Kelly
- Garry Davey - Doctor
- J. B. Bivens - Security Guard
- J. B. Bivens - Mover
- Laura Bruneau - Sharon Rosman
- Henry Beckman - Brad Holland
- Jan Burrell - Elizabeth Doyle
- Frank Cassini - Miguel Enriquez
- David Hurtubise - Bernie
- David Mylrea - Boogeyman
- Jo Bates - French Mother
- Ric Reid - Coroner
- Brent Chapman - Officer
- Angela Gann - Ed's Wife
- Saul Rubinek - Professor Hugaro
- Saul Rubinek - Aaron Zgierski
- Mark McCracken - Jailer
- Tammy Isbell - Judy Hudson
- Veena Sood - Dr. Katzman
- Akiko Morison - Megan Halliwell
- Terence Kelly - General
- Terence Kelly - Oscar Reynolds
- Maxine Guess - Jenny Claridge
- Stephen Fanning - Karl
- Jason Gray-Stanford - Dylan Venable
- Jason Gray-Stanford - Airman
- Ken Kramer - Judge Clancy
- Tanya Allen - Amy Barrett
- Tanya Allen - Lisa
- Debbie Podowski - Tali MacGregor
- Debbie Podowski - Justine Vallé
- Britt McKillip - Sara Kohler
- Britt McKillip - Brook Bouton
- Molly Parker - Jennifer
- Elisabeth Rosen - Nadia Torrance
- Rick Ravanello - Marcus
- Rick Ravanello - Driver
- Kate Robbins - Perry
- Nicole Oliver - Heather Cattrell
- Nicole Oliver - Jill Cooper
- D. Neil Mark - Guard
- David Birznieks - Horner
- Rob Morton - F.B.I. Agent #2
- Walter Marsh - Dr. Lambert
- Walter Marsh - Dr. Sam O'Keefe
- Mar Andersons - Student
- Mary Beth Rubens - Fran Blake
- David Warner - Bill Trenton
- David Warner - Inspector Harold Langford
- Ryan Slater - Timmy Blake
- Pat Bermel - Dr. Reid
- Sean Campbell - Police Officer
- Tobias Mehler - Nicky Reeves
- Tobias Mehler - Eric Nichols
- Johnny Cuthbert - Detective
- Tamsin Kelsey - Victorine
- Tamsin Kelsey - Dr. Glass
- Jano Frandsen - Taylor
- A.C. Peterson - Motel Manager
- Michael Shanks - Dr. Will Olsten
- Michael Shanks - Melburn Ross
- Jessica Harmon - Little Girl
- Jessica Harmon - Tali
- Brian Knox McGugan - Paramedic #1
- Kevin McNulty - Everett Costello
- Kevin McNulty - Dr. Leiberman
- Kevin McNulty - Commander
- Ingrid Tesch - Paramedic #2
- Wren Roberts - Orderly
- Bill Finck - Herman Fitch
- Bruce Harwood - Technician
- Bruce Harwood - Dr. Avery Strong
- Bruce Harwood - Miles Pendergast
- Bruce Harwood - Dr. Norris
- Joel Grey - Dr. Nathan Seward
- Joel Grey - Gideon Banks
- Don Thompson - Doc
- Don Thompson - Max Buford
- Bob Wilde - Lab Tech
- Paul Anthony McLean - Dr. Phillips
- Gillian Carfra - Angie
- Jane MacDougall - Marianne Dobson
- Lynda Boyd - Marie Venable
- Lynda Boyd - Danielle Buchanan
- Austin Basile - Student #2
- Adrian G. Griffiths - Boromir
- Adrian G. Griffiths - Warren
- Paul Hubbard - Officer Scovil
- Robbi Chong - Teresita Arboleda
- Robbi Chong - Hope Wilson
- David Bloom - Expert
- Ewan 'Sudsy' Clark - Congressman Nelson Braddock
- David Lovgren - Eric Tanner
- David Lovgren - Evan
- Michael MacRae - Greg Tilman
- Alison Matthews - Karen Dunn
- Claire Riley - News Anchor
- Claire Riley - Dr. Egan
- James Wilder - Raymond Dalton
- Peter Bryant - Geoff
- Peter Bryant - Mike
- Peter Bryant - Commander Sullivan
- Colleen Winton - Patricia Fowler
- Colleen Winton - Spokeswoman Adrian Wheeler
- Lorretta Bailey - Sister Angelique
- Warren Takeuchi - Male Med Tech
- Ken Camroux-Taylor - Dr. Madison
- Ken Camroux-Taylor - George Fallson
- Ken Camroux-Taylor - Admiral Jones
- Jeremy Hart - Henry Walker
- L. Harvey Gold - Dr. Merritt
- L. Harvey Gold - Dr. Greeson
- John Tench - Collins
- John Tench - Alex
- John Tench - Scarred Man
- James Bell - Drunk Executive
- Kamilyn Kaneko - Kelly
- Kamilyn Kaneko - Receptionist
- Patrick Stevenson - Jake Hart
- Charles Andre - Evan
- Barry W. Levy - Vila
- Barry W. Levy - David Cohen
- Barry W. Levy - Jules Mason
- Barry W. Levy - Colonel Bell
- David Longworth - Robert Beck
- David Longworth - Preacher
- Bethoe Shirkoff - Mrs. Peal
- Katya Gardner - Bethany Wallace
- Philip Granger - Calvin Taylor
- Sean Allan - Priest
- Susan Hogan - Krenn
- Susan Hogan - Dr. Marissa Golding
- Susan Hogan - Phoebe Collins
- Terry Howson - Alien
- Dean Marshall - Captain William Hinman
- Dean Marshall - Corporal Hanford
- Kate Vernon - Judy Warren
- Kate Vernon - Tricia Lange
- Vincent Hammond - Koltok / Megwan
- Len Cariou - Doc Wells
- Len Cariou - Father Anton Jonascu
- Lindsay Bourne - Administrator
- Frank Whaley - Henry Marshall
- Frank Whaley - Zig Fowler / Cliff Unger
- Bill Cobbs - Joe Dell
- Bill Cobbs - Second Elder - Prisoner No. 91777
- Richard Lautsch - Eddie
- Rick Burgess - Sam
- Alan Robertson - Dr. Minkoff
- Richard Sargent - Carl Haven
- Elan Ross Gibson - Woman
- Stephen Tibbetts - Campus Cop
- Wally Dalton - Jason
- Patrick Keating - Technician
- Patrick Keating - GX-17
- Brennan Kotowich - Young Mark
- Adam J. Harrington - Puppet Show Host
- Adam J. Harrington - Billy Valentine
- Adam J. Harrington - Ty Chafey
- Lenno Britos - Man in Bathroom
- Doron Bell - Cory Izacks
- Kerry Sandomirsky - Kristen O'Keefe
- Kerry Sandomirsky - Mary
- Eric Keenleyside - Friedkin
- Eric Keenleyside - Peters
- Eric Keenleyside - Major Ford
- Alexander Boynton - Ex Con
- Harrison Coe - John Arkelian
- Harrison Coe - Man
- Crystal Verge - Hall
- Paula Shaw - Executive
- Paula Shaw - Mrs. Janus
- Ben Immanuel - Electrician
- Ben Immanuel - Blanco
- Robyn Driscoll - Detective
- Campbell Lane - Roland Baker
- Campbell Lane - Noel Bachman
- Adrien Dorval - Convict #1
- Brett Stone - Michelle
- John Gilbert - Dr. Valerian
- Michelle Beaudoin - Jessie Wells
- Michelle Beaudoin - Beth
- Dean Balkwill - Willy
- Liam Ranger - Justin Highfield
- Andrew Wheeler - Tony Blake
- Andrew Wheeler - Gary
- Bill Dow - Dr. Keeler
- Bill Dow - Doc Fink
- Carrie Cain-Sparks - Nurse
- Suki Kaiser - Cheryl
- Kate Twa - Dr. Annaud
- Peta Brookstone - Waitress
- Catherine Swing - Reporter #2
- Catherine Swing - Nurse
- Bart Anderson - Doctor
- Bart Anderson - Townsman
- Christopher Bolton - Orderly Grant
- Adrian Holmes - Soldier
- Adrian Holmes - James
- Michael Cram - Father
- Michael Cram - McKenna
- Louva Meloche - Annie
- Ken Ryan - Leader
- Victor Garber - Dr. Edward Normandy
- Victor Garber - Dr. Ben McCormick
- Jean Daigle - NWA Spokesperson
- Robert Lewis - Gould
- Robert Lewis - Commander Guy LeClerc
- Robert Lewis - Miguel
- Robert Lewis - Jake Sternlight
- Peter Yunker - Instructor
- Peter Yunker - Palmer
- Andrew McIlroy - Hal Kaplan
- Andrew McIlroy - Pallas Demon
- Ron Halder - George White
- Ron Halder - Lab Assistant
- Zook Matthews - Bartender
- Micki Maunsell - Dolly Kellerman
- Klodyne Rodney - Reporter
- Klodyne Rodney - Tyler Buttram
- Catherine Mary Stewart - Joanne Sharp
- Catherine Mary Stewart - Brooke Miller
- David James Lewis - Deputy
- David James Lewis - Will Carson
- David James Lewis - Joe Oakridge
- Heather Hanson - Young Helen
- Heather Hanson - Archer
- Michael Reid MacKay - Alien #1
- Kelly Aluise - Alien #2
- Dwight McFee - Bruce Johnson
- Dwight McFee - Ring Announcer
- Colleen Rennison - Jillian Rosman
- Colleen Rennison - Young Girl
- Michael Riley - Jon Tarkman
- Michael Riley - Gerard
- Derek de Lint - High Centurion Sulat Ray
- Derek de Lint - Carl van der Meer
- Michael Ontkean - Dr. Field
- Michael Ontkean - Dr. Charles McCamber
- Edward Diaz - Derek
- Louis Ferreira - Winston Meyerburg
- Louis Ferreira - Father John Royce
- April Telek - Shirley Baxter
- April Telek - Young Lucy
- Ellis Williams - Donald
- Jill Teed - Tory Beth Walters
- Jill Teed - Gwen Hutchinson
- Jill Teed - Carolyn
- Sharon Alexander - Angry Woman
- Sharon Alexander - Girl Hostage
- Anna Hagan - Dr. Riddle
- Laura Harris - Sarah Hayward
- Laura Harris - Mona Lisa 37X
- Ryan Taylor - Vic
- Tom Cavanagh - Carl Toman
- Tom Cavanagh - Vance Ridout
- Jonathan Whittaker - Colonel Bowen
- Lorena Gale - Doctor
- Lorena Gale - Committee Member
- Lorena Gale - Louise
- Douglas Newell - Principal
- Andrew Johnston - Warden Taylor
- Andrew Johnston - DeWitt
- Andrew Johnston - Mr. Hagen
- Jon Chardiet - Moss
- Preston Maybank - Hank
- Johanna Osborne - Cashier
- Erich Anderson - Evan Robert Cooper
- Erich Anderson - Dr. Deanston
- Roman Podhora - Commander Louis Vidwell
- Martin Cummins - Jack Burrell
- Martin Cummins - Esterhaus
- Tatiana Chekhova - Commander Lara Nabakov
- Joe Pascual - Paramedic
- Joe Pascual - Lt. Marquez
- Zinaid Memišević - Young Man
- Ian Tracey - Mr. Tarkman
- Ian Tracey - Declan McMahon
- Bill Croft - Officer Fletcher
- Bill Croft - Gabriel
- Nick Mancuso - Martin
- Nick Mancuso - Father
- Colin Lawrence - Technician
- Joel Palmer - Andrew Rosman
- Joel Palmer - Jesse Venable
- Joel Palmer - Phillip
- Danny Wattley - Dennis Cameron
- Danny Wattley - Orderly #2
- Althea McAdam - Dr. Behrens
- Althea McAdam - Woman
- Scott Swanson - Kyle Haller
- Scott Swanson - Reverend Leblanc
- Scott Swanson - General Baker
- Scott Swanson - Emil Dobkins
- Scott Swanson - Silver-Haired Man
- Joanna Piros - TV Interviewer
- Joanna Piros - Reporter #1
- Joanna Piros - TV Newscaster
- Joanna Piros - News Anchor
- Jim Byrnes - Merlin
- Jim Byrnes - Gary Latimer
- Richard Leacock - Taylor
- Richard Leacock - Dairy Guard
- Miguel Fernandes - Captain Tavernier
- Michael Todd - Alien
- Mitchell Laurance - Mason Stark
- Michael Ironside - Ambassador Prosser
- Michael Ironside - Gen. Quince
- Matthew Laurance - Mr. Stark
- Jim Swansburg - Man
- Rob Daprocida - Security Guard #2
- Adrian Pasdar - Tanner Brooks
- Claudette Mink - Jessica Brooks
- Fulvio Cecere - Det. Richard Jacobs
- Fulvio Cecere - Stottlemeyer
- Fulvio Cecere - Major
- Angela Moore - African American Woman
- Angela Moore - Nurse #1
- Angela Moore - Rutherford
- Tom Heaton - Red
- Tom Heaton - Crazed Man
- Tom Heaton - Josiah Miller
- Tom Heaton - Jim
- Pat Morita - Michael Chen
- Joseph Gordon-Levitt - Zach Henniger
- Joseph Gordon-Levitt - Teenage Boy
- Douglas Smith - Douglas
- David Neale - Security Guard
- David Neale - Commander Richard Gordon
- David Neale - Evan Branch
- Paul Carson - Reporter #1
- Don MacKay - Pat Dooley
- Don MacKay - Ollie Gibb
- Don MacKay - Dr. Link
- Jessica Steen - Gina Beaumont
- Jessica Steen - Stephanie Sawyer
- Jessica Steen - Kathrine
- Lori Fetrick - Helen
- Scott Owen - Robber
- Scott Owen - Collins
- Scott Owen - Gunman
- Melissa Gilbert - Teresa Janovitch
- Jeremy Ratchford - Sgt. Adam Sears
- Laurie Murdoch - Quisling
- Laurie Murdoch - Lawrence
- Tim Guinee - Corporal Charles Pendelton
- Lorraine Landry - Female Med Tech
- Lorraine Landry - Deirdre Laird
- Kirsten Alter - Sharon
- Kirsten Alter - Pelé
- Gina Chiarelli - Doctor #2
- Gina Chiarelli - Eileen Bowman
- Alex McArthur - Josh Butler
- Chilton Crane - Pregnant Woman
- Chilton Crane - Catharine McCarty
- Chilton Crane - Elaine Tenzer
- Teryl Rothery - Janet Brevson
- Teryl Rothery - Dr. Lucy Cole
- Noah Heney - James Kendal
- Noah Heney - Man's Father
- Grant Heslov - Todd
- William deVry - Ben
- William deVry - Craig Swenson
- William deVry - Bartender
- Lesley Ewen - Nurse Sally Scofield
- Lesley Ewen - Mrs. Dell
- William MacDonald - FBI Special Agent Grant
- William MacDonald - Gary Rosman
- William MacDonald - Mugger
- Caroline Elliott - Allison James
- Brenda McDonald - Mrs. Eikenberry
- Brenda McDonald - Old Arthritic Woman
- Lachlan Murdoch - John Virgil Jr.
- Lachlan Murdoch - Ma'al
- James Marsden - Brav
- Boyan Vukelic - Roan
- David Lloyd Austin - Admiral Sergei Yurov
- David Lloyd Austin - Mistoslav Krupchik
- Ryan DeBoer - Young Louis
- Constance Barnes - Doctor
- Brent Stait - Wayne
- Brent Stait - Vince Baxter
- Lou Diamond Phillips - Captain Cotter McCoy
- Robert Joy - Dr. Greg Olander
- Patricia Harras - Debbie
- Patricia Harras - Amy
- Scott Kraft - Colonel Pete Butler
- Teri Polo - Sally McCoy
- John McConnach - Commando
- Awaovieyi Agie - Guard
- Jonathan Scarfe - Charlie Walters
- Jonathan Scarfe - Vince Chance
- Brent David Fraser - Graham
- Geraint Wyn Davies - Dr. David LaSalle
- Geraint Wyn Davies - Sheriff Grady Markham
- Dean Mckenzie - Newscaster
- Dean Mckenzie - Kellar
- Joy Coghill - Jean
- Benz Antoine - Larue
- Benz Antoine - Security Guard #1
- Benz Antoine - Fence Guard
- Benz Antoine - Sergeant
- Arye Gross - Bernard Selden
- Jeffrey DeMunn - Dr. Adam Pike
- Kyra Azzopardi - Catherine
- Kyra Azzopardi - Hannah Zgierski
- Kyra Azzopardi - Kate Martin
- Mark Gibbon - Bailiff
- Mark Gibbon - Overseer #2
- Mark Gibbon - Male Vorak
- Darren Moore - Gangmember
- Dan Shea - Cop
- Dan Shea - Old Man / Cop
- Ingrid Kavelaars - Nicole
- Ingrid Kavelaars - Angie Palmer
- Zachary Ansley - Adrielo
- Zachary Ansley - Alien
- Steve Bacic - Roy
- Steve Bacic - Griff
- Jim Smith - Mr. Wilkes
- Linda Darlow - Dr. Thoroughgood
- Camille Mitchell - Leader of Hyacinth
- Camille Mitchell - Mother
- Alvin Sanders - Chaplain
- Judith Maxie - Judge Peale
- Judith Maxie - Judge
- Judith Maxie - Mayor Grant
- Brent Sheppard - F.B.I. Agent #1
- Brent Sheppard - Man on TV
- Gregory Harrison - Dr. Larry Chambers
- Kim Huffman - Amanda Harper
- Doug Jones - Elder Alien
- Doug Jones - Alien #1
- Doug Jones - Alien / Alien Doctor
- William Atherton - Franklin Murdoch
- David Allan Pearson - Stanley Fenton
- Scott McNeil - Astronaut
- Scott McNeil - Silloin / Linna (voice)
- Jay Brazeau - Bernard Katz
- Jay Brazeau - Dr. George Bader
- Patricia Mayen-Salazar - Carmen Ortega
- Frank C. Turner - Elder
- Frank C. Turner - Mikulak
- Frank C. Turner - Luther
- Frank C. Turner - Old Man
- Betty Linde - Helen Darnell
- Betty Linde - Sylvia
- Brett Cullen - Dr. James Martin
- Stellina Rusich - Sharon
- Sarah Strange - Lisa
- Sarah Strange - Rachel Connors
- Sarah Strange - Tara
- Kevin Tighe - General
- Chris Nelson Norris - Captain Litvak
- Gerry Rousseau - Bum
- Gerry Rousseau - Jimmy
- John Pyper-Ferguson - Brian Chason
- John Pyper-Ferguson - Dr. Kenneth Vaughn
- Gary Hetherington - Chief Davis
- Doug Abrahams - Foreman
- Doug Abrahams - Sheriff O'Brien
- Lochlyn Munro - Waters
- Lochlyn Munro - Captain Eric Woodward
- Ken Pogue - Ian Harper
- Ken Pogue - Dean Hardwick
- Ken Pogue - Mr. Jones
- Kim Coates - Dave Stockley
- Kim Coates - Colonel Sage
- Brennan Elliott - Tom
- Maria Louisa Figura - Virginia Masters
- Maria Louisa Figura - Inga
- David Cubitt - Colonel Faber
- David Cubitt - Curtis Grainger
- David Cubitt - Kevin Stein
- Derek Lowe - Student
- David Keith - Major Mercer
- Scott Hylands - Governor Oleaga
- Scott Hylands - Wayne
- Scott Hylands - Dr. Howard Sarrazin
- Scott Hylands - Col. Roger Tennent
- Anthony Ulc - Roger Bowden
- Nadia Capone - Miranda
- John 'Bear' Curtis - Blacksmith
- John 'Bear' Curtis - Bum
- Maxine Miller - Helen
- Maxine Miller - Mrs. Fitzgerald
- Dale Wilson - Frank McKenna
- Dale Wilson - NORAD General Morehouse
- Dale Wilson - General Langston Chase
- Julie Harris - Hera
- Katie Stuart - Phoebe
- Karin Konoval - Sarah
- Jenny-Lynn Hutcheson - Nomi
- Kristin Lehman - Larissa Whitehouse
- Kristin Lehman - Janet Marshall
- Kristin Lehman - Lorelle Palmer
- Kristin Lehman - Katya Rubinov
- Julie Bond - Pontella
- Michelle Hart - Enya
- Malcolm Stewart - Daniel Tenzer
- Malcolm Stewart - Phil Krepuski
- Malcolm Stewart - Joel Haas
- Malcolm Stewart - Garrison
- Nadia-Leigh Nascimento - Elysse
- Harry Hamlin - Ford
- Tom Butler - Mr. Evans
- Tom Butler - Dr. Werner
- Tom Butler - General Morehouse
- Tom Butler - Charlie Bouton
- Tom Butler - Charlie Rogers
- Bridget O'Sullivan - Louise McDonnaugh
- Robert Guillaume - Mr. Brown
- Gabrielle Miller - Charlotte Nichols
- Gabrielle Miller - Wendy Seymour
- Gabrielle Miller - Megan
- Arnie Walters - Father Pat
- Arnie Walters - Committee Member
- Nicholas Harrison - Head of Security
- Michael St. John Smith - Dean Irwin
- Michael St. John Smith - Dr. Richard Morgan
- Michael St. John Smith - Angus Wheaton
- Michael Jonsson - Delta #2 Leader
- Peter Wilds - Dean
- Eli Gabay - Faber
- Patricia Dahlquist - Doctor
- Emmanuelle Vaugier - Shal
- Emmanuelle Vaugier - Lisa Dobkins
- Steven Bauer - Sgt. Waylon Dumar
- Brandy Ledford - Dr. Elana Chomsky
- Russell Ferrier - Cop
- Russell Ferrier - Detective
- Russell Ferrier - Game Warden
- Cameron Graham - Lt. Christopher Valentine
- Garwin Sanford - Senator Meade
- Garwin Sanford - Peter Chandler
- Garwin Sanford - Dom Pardo
- Sarah Deakins - Megan
- Sarah Deakins - Amanda Nance
- David McNally - Roy Chance
- David McNally - Thomas Vallé
- David McNally - Pete
- David McNally - Shak-El
- David Glyn-Jones - Poker Pal
- David Glyn-Jones - Mr. Westbrook
- Robin Shou - Major Ronald Neguchi
- Alex Diakun - Nicholas Prentice
- Alex Diakun - Quasga
- Alex Diakun - Shopkeeper
- Alex Diakun - Mr. Wilkes / Father Claridge
- Alex Diakun - Moses Saxon
- Alex Diakun - Minister
- Robert Moloney - Lab Technician
- Robert Moloney - Veeter
- Robert Moloney - Agent Pinter
- Robert Moloney - Corporal Beauregard Larouche
- Eric Schneider - High Commander Reese
- Eric Schneider - The Voice
- Eric Schneider - Triune
- Eric Schneider - Detective Barclay
- Eric Schneider - Alien Inquisitor
- Eric Schneider - Dr. Golden
- Eric Schneider - Dr. Miles Osgoode
- Eric Schneider - Dr. Stanley Miller
- Chantal Strand - Young Girl
- Nancy Sorel - Dana van Owen
- Nancy Sorel - Page Houghton
- Caroline Goodall - Rebecca
- Dax Belanger - Second Protester
- Dax Belanger - Security Guard
- Joseph Kell - David
- René Auberjonois - Dlavan
- Michael Ryan - Rex Andrews
- Michael Ryan - Thomas Langley Russell
- Kevin Hansen - Young Man
- Kevin Hansen - Deputy
- Kristian Ayre - T'sha
- Aaron Pearl - Lt. Winters
- Aaron Pearl - Roger Beckersly
- Aaron Pearl - Clark
- Maurice Godin - Dr. Noah Phillips
- Ty Olsson - Franklin
- Ty Olsson - Mike
- Harve Presnell - Greg Matheson
- Lisa Maris - Meredith Phillips
- Fiona Loewi - Young Barbara Matheson
- Barbara Rush - Barbara Matheson
- Michael Tiernan - Major Braithwaite
- Michael Tiernan - Vincent
- Clare Lapinskie - Claire
- Michael Kopsa - Curtis Sawyer
- Michael Kopsa - Commander Ivers
- Michael Kopsa - Engineer
- Michael Kopsa - Detective Broder
- Gordon Tipple - Detective #1
- Gordon Tipple - Finerman
- P. Lynn Johnson - Vera Dobkins
- P. Lynn Johnson - Mrs. Hagen
- P. Lynn Johnson - Lucy
- Adam Baldwin - Major James Bowen
- Barbara Eve Harris - Colonel Samantha Elliot
- Dee Jay Jackson - Guard
- Dee Jay Jackson - Joe
- Gordon Currie - Stadetski
- Joan Chen - Major Dara Talif
- Linden Banks - Hal Taylor / Sid Camden
- Linden Banks - Dr. Thomas Somerset
- Mina E. Mina - Colonel Paz
- Brendan Stitchman - Private Juanas
- Maria del Mar - Jennifer Rigny
- Chris Mulkey - Mike
- Jennifer Sterling - Nurse
- Jennifer Sterling - Janet
- Jennifer Sterling - Detective Meacham
- Maurice Dean Wint - Capt. Roger Kimbro
- Maurice Dean Wint - Jesha
- Belinda Metz - Karen
- Peter DeLuise - Cop
- Paul Jarrett - Dr. Franklin Dreiden
- Paul Jarrett - Dr. Mauser
- Nancy Kerr - Dr. Allensworth
- Donny Lucas - Hornet
- John Innes - Priest
- John Innes - Teacher
- Nana Visitor - Cecilia Fairman
- Dana Pemberton - Security Guard
- John Wardlow - Dr. Blake
- D. Harlan Cutshall - Guard
- D. Harlan Cutshall - Captain
- Kathleen Duborg - Hope
- Kathleen Duborg - Karen McDonald
- R. Nelson Brown - Bum
- R. Nelson Brown - Bartender
- Cynthia Nixon - Trudy
- Paul Magel - Navy Frogman
- Paul Magel - Caleb
- Daryl Shuttleworth - Burns
- Larry Musser - Larry Leonard
- Larry Musser - Clerk
- Larry Musser - Maj. Samuel Harbeck
- Larry Musser - Detective Pete Button
- Larry Musser - Jack Parsons
- Larry Musser - Dr. Evan Swift
- Allan Zinyk - Eldon DeVries
- Charles Payne - McCoy
- Kasper Michaels - Bartender
- Nancy Sivak - Eldon's Wife
- David Kaye - News anchor - Marcus Gilbert
- David Kaye - Ed Tupelo
- Nathaniel DeVeaux - Col. Birch
- Nathaniel DeVeaux - Captain
- Nathaniel DeVeaux - Roger Cress
- Nathaniel DeVeaux - Don Hattaway
- Nathaniel DeVeaux - Security Captain
- Chantal Conlin - Kylie Laird
- Don S. Davis - General Callahan
- Don S. Davis - Detective Wilson
- BJ Harrison - Administrator
- Kimberly Unger - Reporter #1
- Ross Douglas - Andy Morgan
- Ingrid Torrance - Becky
- Timothy Webber - Dr. Willard Haley
- Timothy Webber - Dep. Middleton
- Timothy Webber - Martin Nash
- Lloyd Berry - Abraham Lincoln Re-Enactor
- Lloyd Berry - Mike Kellerman
- Marc Baur - Board Member
- Phillip Mitchell - Mugger
- Phillip Mitchell - Security Man
- Garvin Cross - R & R Leader
- Garvin Cross - Agent Bauer
- Garvin Cross - Ralph Sutton
- Garvin Cross - Officer #1
- Garvin Cross - Lt. Jackson
- Garvin Cross - Hawkes
- Hiro Kanagawa - Ron Hikida
- Hiro Kanagawa - Tali
- Ted Shackelford - High Secretary Paul Kohler
- Blair Slater - Ken Kohler
- Marina Sirtis - Olivia 'Liv' Kohler
- Lee Taylor - Bailiff
- Lee Taylor - Colonel Lynne
- Gillian Barber - Fisk
- Gillian Barber - General
- Gillian Barber - Lt. Bateson
- Jane Spence - Female Rebel
- Peter Outerbridge - Zach Griffiths
- Peter Outerbridge - Dr. Andy Groenig
- Peter Outerbridge - Scientist
- Peter Outerbridge - Ned Bailey
- Jake T. Roberts - Colonel Vaux
- Susannah Hoffmann - Janice Claymore
- Aaron Smolinski - Adam Finlay
- Bob Dawson - Mr. Walker
- Bob Dawson - Sheriff Clay
- Catherine Lough Haggquist - Eileen
- Catherine Lough Haggquist - Reporter
- Alec Willows - Warner Oland
- Barbara Tyson - Nancy Henniger
- Barbara Tyson - Carrie Emerson
- Barbara Tyson - Dr. Kate
- Darryl Scheelar - Sergeant Laughton
- Darryl Scheelar - Gorum
- Trevor White - Vince Carter
- Jennifer Copping - Julie Alger
- Jennifer Copping - Corporal Harrier
- Blu Mankuma - Captain John Owens
- Blu Mankuma - Stanley
- Blu Mankuma - 2013 U.S. President
- Pamela Perry - Madelaine Parkhurst
- Kevin Hayes - Reporter #2
- Kavan Smith - Quarterback
- Kavan Smith - Lt. O'Neill
- Kavan Smith - Dominic Langton
- Kavan Smith - Allan
- Kavan Smith - Harrison Taylor
- Jerry Wasserman - William Talbot
- Jerry Wasserman - Gunther Van Owen
- Jerry Wasserman - Dr. Silcase
- Brian Jensen - Cole
- Andrew Airlie - Don
- Andrew Airlie - Dr. Kevington
- Andrew Airlie - F.B.I. Agent Corey Lonn
- Andrew Airlie - Jonathan Morris
- Andrew Airlie - Marcus Fellows
- Marie Stillin - Allison
- Marie Stillin - Governor Mudry
- Carmen Aguirre - Vagrant #1
- Ed Evanko - Jim Holbrook
- Ed Evanko - Preacher
- Jimmy Herman - Mickey
- Roger Cross - Lt. Lockhart
- Roger Cross - Kevin Flynn
- Roger Cross - Jon
- Roger Cross - Bartender
- Jeff Burnett - Terry
- Jerry Walliser - Father
- Julie Patzwald - Tara Vanatter
- Julie Patzwald - Cammi
- Ronin Wong - Dr. Chan
- Ronin Wong - Doctor #1
- Sheila Paterson - Leona Fletcher
- Rondel Reynoldson - Esme O'Brien
- Gerard Plunkett - George
- Gerard Plunkett - Gideon
- Gerard Plunkett - Admiral Birch
- Luc Corbeil - Driver
- Clare Sims - Lady Ellen
- Eliza Norbury - Lady Sophie
- Robert Saunders - Appleby
- Marnie Alton - Elizabeth 'Lizzie' Stride
- Duncan Fraser - General Post
- Duncan Fraser - Coach Terni
- Colin Skinner - Worthington
- Terry David Mulligan - Chancellor Duncan Wilder
- Terry David Mulligan - Det. Landers
- Scott Elam - Lord Reston
- Jason Gaffney - Kirk
- Jason Gaffney - Joe Benton
- Brian Linds - Reporter
- Ken Tremblett - Michael Dowd
- Ken Tremblett - Businessman
- Ken Tremblett - Tom
- Rob Freeman - Milus O'Brien
- Rob Freeman - Captain Rosen
- Cheryl Wilson - Cynthia Walker
- Cheryl Wilson - Nurse Rebecca
- Bonnie Catterson - Blonde Woman
- Carmen Casanova - Street Prostitute #1
- Maya Nadine - Street Prostitute #3
- Vincent Gale - Dooley McMahon
- Vincent Gale - Walt
- Vincent Gale - Corporal Hawthorne
- Apollonia Vanova - Female Prisoner
- Sue Astley - Grace
- Jonathan Walker - Brent Secor
- Britt Irvin - Judith Wilder
- Britt Irvin - Katrine Houghton
- Dave Adams - Desmond Shiff
- Peter Kelamis - Stan Draper
- Peter Kelamis - Brain Wakefield
- Greg Thirloway - James Feind
- Sean Millington - Delta #1 Leader
- Sean Millington - Guard
- Madeline Elder - Self-centered Woman
- Stacy Grant - Kara Delaney
- Corrine Koslo - Abby
- Nicole Robert - Librarian
- Winston Brown - Male Staff Member
- Winston Brown - Sergeant Nichols
- Rice Honeywell - Timothy Laird
- Rice Honeywell - Co-Worker
- Shaun Johnston - Cop
- Shaun Johnston - O'Brien
- Shaun Johnston - Parker
- Candus Churchill - Nurse
- Maya Massar - Daria Michaels
- William B. Davis - John Wymer
- William B. Davis - Dr. Frank Biemler
- William B. Davis - Ed
- Biski Gugushe - Chief Technician David
- Biski Gugushe - James
- Doris Chillcott - Mrs. Westbrook
- Woody Jeffreys - Male Model
- Woody Jeffreys - Beck Sanders
- Ocean Hellman - Miriam Turner
- Ocean Hellman - Fern
- Ocean Hellman - Pregnant Woman
- John Moore - Butler
- Ian Robison - Craig
- Ian Robison - Grant Kildale
- Beverley Elliott - Holly
- Beverley Elliott - Celeste
- Christina Jastrzembska - Mary Cummings
- Christina Jastrzembska - Karen Miller
- Christina Jastrzembska - Sonja
- Myles Ferguson - Brad
- David Kopp - Josh Buchanan
- Will Sanderson - Nelson Tyler
- Chris Wilding - Mean Kid #1
- John Novak - Dave Pettigrew
- John Novak - Tom Grant
- John Novak - Voice of Adam (voice)
- John Novak - Dr. Stansfield
- Tim O'Halloran - Security Chief
- Tim O'Halloran - Man #1
- Jonathan Ndukwe - Mean Kid #2
- Sal Sortino - Janitor
- Anthony Sherwood - Hank Dell
- Eleana Johnson - Edna Vanatter
- Duane Keogh - Roger Nygard
- Matthew Harrison - Orderly
- Tom Pickett - Security Guard
- Barbara Dyke - Woman
- Howard Siegel - Bum
- Howard Siegel - Superintendent
- G. Patrick Currie - Young Harris
- G. Patrick Currie - Ep
- G. Patrick Currie - Ben
- Natasha Vasiluk - Alexandra Nevsky
- Zoran Vukelic - Hector
- Jim Shield - Duro
- Derek Peakman - Professor Wylie
- Derek Peakman - Dr. Pastore
- Ian Brown - Innocuous Man
- Leslie Hope - Weatherman
- Leslie Hope - Darcy Kipling
- Vincent Walker - Boyfriend
- Vincent Walker - Prisoner
- Marcy Goldberg - Council Member Roark
- Marcy Goldberg - Obnoxious Woman
- Stacy Keach - Cord van Owen
- Christian Bocher - Matthew Logan
- Stephen Dimopoulos - Horace Vaughn
- John de Lancie - Donald Finley
- Brock Johnson - Nate Jackson
- Greg Anderson - Dealer
- Nels Lennarson - Deputy
- Antonio Sabàto, Jr. - Chad Warner / Sid Camden
- Matthew Walker - Winston
- Matthew Walker - Trevor Hunter
- Matthew Walker - Terry Walsh
- Matthew Walker - Kra'dok
- Christina Cox - Deb Clement
- Clay St. Thomas - Host on TV
- Clay St. Thomas - Reporter
- Deanna Milligan - Gail
- Adam Goldberg - Sid Camden
- Ted Cole - Chris
- Claude Duhamel - Grant
- Gaetana Korbin - Deb Model
- Devin Douglas Drewitz - Sasha Vadimsky
- Devin Douglas Drewitz - Ty Logan
- Devin Douglas Drewitz - Isaac
- Kevin Durand - Alan
- Moya O'Connell - Girlfriend
- Michael David Simms - The Administrator
- Michael David Simms - Ed
- Tanya Reid - Amber
- Avery Raskin - Boss
- Joyce Erickson - Old Lady
- Ron Selmour - Colonel Kikongo
- Ron Selmour - Carl
- Kristina Matisic - News Anchor
- Kristina Matisic - Reporter
- Linda Ko - Hanna Sheafer
- Rick Dobran - Lieutenant Mason
- John Murphy - Lieutenant
- Rick Roberts - Andrew McLaren
- Laurie Holden - Susan McLaren
- Joe Costa - Jailor
- Bill Mackenzie - Policeman #2
- Obba Babatundé - Dr. Joseph Lennox
- Dean Wray - Alvin Madden
- Dean Wray - Tito
- Tatiana Turner - Kyra Look-Alike
- Curtis Bechdholt - Eddie
- Fiona Scott - Tara Akton
- Chris Lovick - Matt Hooper
- Bobby Stewart - Sheriff Blackwell
- Sarah Hayward - Doris Hooper
- Donna-Lynne Larson - Sally Latimore
- Ron Small - Johnny
- Ron Small - Harold Sanborn
- Christine Elliott - Young Linda
- Mikela Jay - Zoe
- Cathy Weseluck - The Voice of Simon
- Tamara Prescott - Elise Banks
- Deni DeLory - Alexis Worthy
- Deni DeLory - Annie Chapman
- Maureen Thomas - Elizabeth
- Brenda Crichlow - Kayla Powers
- Garfield Wilson - Officer
- Jane Sowerby - Susan
- Jane Sowerby - Ruth
- John Dadey - Special Agent Merton Handy
- Roberta Maxwell - Mrs. Reynolds
- Lyle St. Goddard - Paramedic
- James Tsai - Technician
- Moneca Stori - Technician
- Tate Donovan - Tom Seymour
- Betty Phillips - Sylvia Walker
- Stephen E. Miller - Lt. Colonel Hickox
- Michasha Armstrong - Hmong
- Michasha Armstrong - Policeman
- Jack Klugman - Joe Walker
- Jayne Paterson - Technician
- Suzy Joachim - Catherine Walsh
- Michael Tomlinson - Will Sunderland
- CCH Pounder - The Stranger
- Keith Martin Gordey - Pilot
- Byron Lucas - Augie Berger
- Dion Luther - Gordon 'Gord' Knight
- Corbin Bernsen - Virgil Nygard
- D.B. Sweeney - Scott Bowman
- Eric Breker - Peter Bowman
- Brenda Campbell - Joanna Bowman
- Patricia Idlette - Waitress
- Chris Duggan - Man #2
- Kenneth G. McIntyre - Old Timer
- Greg Rogers - Reverend Samuel Garland
- Carrie Gibson - Choir Singer
- Scott Bellis - Major Drummond
- Meat Loaf - Col. Angus Devine
- David Storch - Major Hinton
- Keith Provost - Dealership Manager
- Keith Provost - Bartender
- Kwesi Ameyaw - Policeman #1
- Kwesi Ameyaw - Dr. Adam Meares
- David Abbott - Herbert Lowry
- Jordan Weller - Teen #2
- Jordan Weller - Zack
- Reg Tupper - Walt Coghlan
- James Crescenzo - Sylvano
- James Crescenzo - Host
- JR Bourne - Dell Tinker
- Marcel Maillard - Pastor Wickham
- Marcel Maillard - Homeless Man
- Ian Marsh - Medusan Defendant
- Ian Marsh - Hing Centurion
- John Amos - Peter 'Yas' Yastrzemski
- Irene Karas - Mickey
- Brendan Beiser - Ben Powell
- Tiffany Lyndall-Knight - Technician
- Kelly Rutherford - Rachel
- Brenda James - Marcy Newhall
- Jesai Jayhmes - Lou Wolsky
- Sam MacMillan - Pete
- John R. Taylor - Old Man Rivers
- John R. Taylor - Leon
- Laara Ong - Elise
- Karina Carreck - Nurse
- Karina Carreck - Secretary
- Kimberley Warnat - Candace Miller
- Giacomo Baessato - Russ Miller
- Alf Humphreys - Dennis
- Michael Daingerfield - Delivery Man
- Graham Wardle - Man
- Jade Pawluk - Clay
- Patrick McManus - Dr. Mandel
- Myfanwy Meilen - Beckett's Wife
- Aaron Joseph - Basketball Kid
- Erica Carroll - Elizabeth Andrews
- Erica Carroll - Nurse
- Erica Carroll - Claudia
- Erica Carroll - Energy Being
- Michael Eklund - Jacob
- Jeremy Van der Driesen - Polk
- Heather Donahue - Claire Linkwood
- Haig Sutherland - Will Monroe
- Haig Sutherland - Roy Evereznak
- Gerry South - Mugger
- Gerry South - Matt
- Elizabeth McLaughlin - Donna
- Enid-Raye Adams - Emily
- Simone Bailly - Administrator
- Samantha McKenna - Debbie
- Jere Burns - Jake Worthy
- Anthony De Longis - Commander McCarty
- Bruce Gray - James Harding
- Joe Maffei - Landlord
- Bill Meilen - Old Drunk
- Thomas Potter - Tattooed Thug
- Mark Brandon - The Gentleman
- Derek Morrison - Deadbeat
- Michael P. Northey - Vern
- Rick Poltaruk - Banjo
- James Ralph - Ominous Man
- Sylvesta Stuart - Ominous Man
- Yvonne Myers - Loretta
- Yvonne Myers - Guard
- Julia Tortolano - Amanda Madden
- Michele Bogdanow - Nurse
- John Treleaven - Investor
- Johnathon Schaech - Andy Pace
- Michelle Harrison - Gabrielle Pace
- Ralph Alderman - Phil
- Kevin Blatch - Jewellery Salesman
- Jeffrey Ballard - Young Boy
- Joanna Going - Dr. Anya Kenway
- Samantha Grant - Mrs. Vadimsky
- Khaira Ledeyo - Jane
- Johannah Newmarch - Nancy LaSalle
- Shawn Reis - Jensen
- Glenn Ennis - Guard
- Igor Morozov - Russian Scientist
- Irene Bedard - Callie Whitehorse Landau
- Greg Evigan - Flight Crew Director James Dreeden
- Monique Mojica - Grandmother
- Helene Joy - Dr. Louisa Kennedy
- Cameron Daddo - Alec Landau
- Jeremy London - Chris
- Rebecca Reichert - Mia
- Jud Tylor - Violet
- Steve Archer - Lead Cop
- Noah Beggs - Prison Guard
- Xantha Radley - Sarah
- Artine Brown - Drunk
- Barbara Pollard - Alice
- Rekha Sharma - Reese
- Ryan Robbins - Richard
- Grace Park - Satchko
- Emy Aneke - James Williams
- Leanne Adachi - Dr. Healy
- Leanne Adachi - Captain Alice Wheeler
- Aaron Craven - ROTC Student
- Lee Tockar - Pothead
- Cory Chetyrbok - Hippie
- Don Kline - Principal
- Anne Marie DeLuise - Miranda
- Robert Freeman - Armstrong
- Carrie Genzel - Lavinia Oleaga
- Todd Sandomirsky - Dov
- Martin Sims - Andy
- Paul Whitney - Bailiff
- Charles Zuckermann - Medusan Chieftain
- Crystal Bublé - Linda
- Stephen Chang - John Li
- Jeremy Guilbaut - Brent Kearns
- Alejandro Rae - Warren
- Harry Rob Bruner - Bryce
- Jonathan Cherry - Andy Wilson
- Allan Gray - Prometheus
- Gus Lynch - Logan
- Rhonda Dent - Young Laura Sinclair
- Christine Kennedy - Candace
- Brandy Kopp - Marilyn
- Neil Schell - Dr. Campbell
- Dallas Thompson - Allyson
- Kevan Ohtsji - Cho
- Talia Ranger - Kaila
- Laara Sadiq - Lt. Conover
- Stephen Spender - Corbett
- Catherine Zak - Jen Ward
- Danny Dworkis - Harry
- Ginger Page - Young Nora
- David Kaye - Young Man
- Manny Coto
- Pen Densham
- Joel Goldsmith
Gary Busey interpreta a Ezra Burnham en la serie.
Mark Hamill interpreta a Dr. Sam Stein en la serie.
María Conchita Alonso interpreta a Marie Alexander en la serie.
Adam Baldwin hace el papel de Major James Bowen.
Ronny Cox interpreta a Lt. Col. Lester Glade en la serie.
Joe Pantoliano hace el papel de Stan Harbinger.
Callum Keith Rennie interpreta a Carlito en la serie.
David Warner interpreta a Inspector Harold Langford en la serie.
Mykelti Williamson interpreta a Dr. Michael Alders en la serie.
Stacy Keach interpreta a Cord van Owen en la serie.
Capítulo disponible en las siguientes plataformas:
