George Sanders
Gen. Armstrong
Maurice Evans
Dr. Matthews / Alien
Patrick Allen
Bob Megan
Neil Connery
Jim Radford
Robert Flemyng
W.C. Baldwin
Pamela Conway
Lorna
Allan Cuthbertson
Hindsmith
Michael Culver
Lt. Bailes
Sally Faulkner
Joanna
Shelagh Fraser
Mrs. Thatcher
Hilary Dwyer
Julie Slade
Dennis Chinnery
Control Officer