Susan Harris
Julie Christie
Alex Harris
Fritz Weaver
Amy
Dana Laurita
Marlene
Michelle Stacy
Baby
Felix Silla
Tiffany Potter
Night Operator
E. Hampton Beagle
Technician
Michael Glass
Barbara O. Jones
Joan Kemp
Monica MacLean
Scientist
Peter Elbling
Housekeeper
Georgie Paul
Walter Gabler
Gerrit Graham
Proteus IV (voice) (uncredited)
Robert Vaughn
Petrosian
Berry Kroeger
Soong Yen
Lisa Lu
Cameron
Larry J. Blake
Royce
John O'Leary
Mokri
Alfred Dennis
Warner
Davis Roberts
Mrs. Talbert
Patricia Wilson
Director
Donald Cammell
Screenplay
Robert Jaffe
Director of Photography
Bill Butler
Visual Effects
Jordan Belson
Stunts
Julie Ann Johnson
Novel
Dean R. Koontz
Producer
Herb Jaffe
Original Music Composer
Jerry Fielding
Editor
Frank Mazzola
Makeup Artist
Don L. Cash
Frank Griffin
Lee Harman
Hairdresser
Dione Taylor
Second Assistant Director
Alan Brimfeld
Assistant Director
Edward Teets
Sound
Jerry Jost
William L. McCaughey
Sound Editor
John Riordan
Special Effects
Tom Fisher
Terry W. King
Glen Robinson
Grant Bassett
Richard L. Froman
Bo Gehring
Ron Hays
Domenic Iaia
James F. Liles
Roger O. Hirson
Associate Producer
Steven-Charles Jaffe
Casting
Jennifer Shull
Production Design
Edward C. Carfagno
Set Decoration
Barbara Krieger
Publicist
Regina Gruss