Maximilian Schell
Dr. Hans Reinhardt
Anthony Perkins
Dr. Alex Durant
Robert Forster
Captain Dan Holland
Joseph Bottoms
Lieutenant Charles Pizer
Yvette Mimieux
Dr. Kate McCrae
Ernest Borgnine
Harry Booth
Tom McLoughlin
Captain S.T.A.R.
Roddy McDowall
V.I.N.CENT. (voice) (uncredited)
Slim Pickens
B.O.B. (voice) (uncredited)
Gary Nelson
Drone with Mask Removed (uncredited)