Natasha Henstridge character Sil
Ben Kingsley character Xavier Fitch
Michael Madsen character Preston Lennox
Alfred Molina character Dr. Stephen Arden
Forest Whitaker character Dan Smithson, Empath
Michelle Williams character Young Sil
Marg Helgenberger character Dr. Laura Baker
Jordan Lund character Aide
Herta Ware character Mrs. Morris
William Utay character Colleague
Don Fischer character Aide
Scott McKenna character Train Hobo
Virginia Morris character Mother
Jayne Luke character Snack Shop Clerk
David K. Schroeder character German Tourist
David Jensen character Conductor
Esther Scott character Female Conductor
Shirley Prestia character Victoria Roth, Ph.D.
David Selburg character Government Man
Melissa Bickerton character Fitch's Secretary
Lucy Rodriguez character Wedding Dress Saleswoman
Scott Sproule character Team Driver
Stogie Kenyatta character Cop
Gary Bullock character Motel Clerk
Susan Hauser character Lab Worker
William Bumiller character Club Bouncer
Caroline Barclay character Drunken Girl
Matthew Ashford character Guy in Club
Anthony Guidera character Robbie, Guy Picking Up Sil
Sara Lise character Screaming Woman
Whip Hubley character John Carey
Patricia Belcher character Hospital Admittance Clerk
Richard Fancy character Hospital Doctor
Leslie Ishii character Hospital Nurse
Marliese Schneider character Abducted Woman
Robert Mendelson character Homeless Man
Pamela Cook character Commercial Model
Lisa Liberati character Bathroom Bimbo
Ed Stone character Waiter
Dendrie Taylor character Marie
Kurtis Burow character Baby Boy
Dana Hee character Creature Performer
Frank Welker character Alien Sil (voice)
Justin Armao character Bystander (uncredited)
Jellybean Benítez character Club DJ (uncredited)
Greg Bronson character Special Forces (uncredited)
Jimmy Chunga character Commando (uncredited)
James Ent character Lt. Steele (uncredited)
Roman Güttinger character Doctor (uncredited)
Christopher Ivins character Soldier (uncredited)
Zak Knutson character Club Doorman (uncredited)
Coati Mundi character Conga Player (uncredited)
Jason Newell character Special Forces (uncredited)