In order to save an assassinated scientist, a submarine and its crew are shrunk to microscopic size and injected into his bloodstream.
Stephen Boyd
Grant
Raquel Welch
Cora
Edmond O'Brien
General Carter
Donald Pleasence
Dr. Michaels
Arthur O'Connell
Col. Donald Reid
William Redfield
Capt. Bill Owens
Arthur Kennedy
Dr. Duval
Jean Del Val
Jan Benes
