Robert Forster
Prof. Paul Corwin / The Clone
Adrienne Barbeau
Margaret Corwin
Ray Milland
Prof. Meredith
David Sheiner
Prof. Sidney Hillstrom
John Lehne
Lt. Merholz
Denise DuBarry
Ann Sweeney
Jack De Mave
Roger
Thomas Bellin
Ed Linnick
Heather Hobbs
Jenny
Eddie Quillan
Watchman
Raye Sheffield
Clone
Russell Shannon
Guard
James Nolan
Dr. Tapler
Madeleine Shaner
Audrey Linnick
Johnny Hock
1st Skater
Thomas McGowan
Andrew Pauletta (uncredited)
John Herman Shaner
Fire Captain (uncredited)
D.A. Young
Lance (uncredited)