The explorer craft USS Palomino is returning to Earth after a fruitless 18-month search for extra-terrestrial life when the crew comes upon a supposedly lost ship, the USS Cygnus, hovering near a black hole. The ship is controlled by Dr. Hans Reinhardt and his monstrous robot companion, but the initial wonderment and awe the Palomino crew feel for the ship and its resistance to the power of the black hole turn to horror as they uncover Reinhardt's plans.
Maximilian Schell
as Dr. Hans Reinhardt
Anthony Perkins
as Dr. Alex Durant
Robert Forster
as Captain Dan Holland
Joseph Bottoms
as Lieutenant Charles Pizer
Yvette Mimieux
as Dr. Kate McCrae
Ernest Borgnine
as Harry Booth
Tom McLoughlin
as Captain S.T.A.R.
Roddy McDowall
as V.I.N.CENT. (voice) (uncredited)
Slim Pickens
as B.O.B. (voice) (uncredited)
Gary Nelson
as Drone with Mask Removed (uncredited)