In order to save an assassinated scientist, a submarine and its crew are shrunk to microscopic size and injected into his bloodstream.
Fantastic Voyage is a 1966 American science fiction adventure film directed by Richard Fleischer and written by Harry Kleiner, based on a story by Otto Klement and Jerome Bixby. The film is about a submarine crew who is shrunk to microscopic size and venture into the body of an injured scientist to repair damage to his brain. In adapting the story for his script, Kleiner abandoned all but the concept of miniaturization and added a Cold War element. The film starred Stephen Boyd, Raquel Welch, Edmond O'Brien, Donald Pleasence, and Arthur Kennedy.