When a scientist is critically injured in a murder attempt by enemy agents, his resulting brain clot can only be operated on by shrinking a submarine and its crew down to microscopic size and injecting them into the scientist's body. They try to destroy to clot from within, but things don't go according to plan...
This science fiction favourite was written by Jerome Bixby (adapted by David Duncan), and at the time was unique in its central minituarisation gimmick. The crew of the Proteus make their way around the body, visiting the heart, the lungs, the ear and, er, the mind (they never travel below the waist, you'll be relieved to know). Unfortunately there's an easy-to-spot saboteur on board to make life difficult for them.
Stephen Boyd is our hero, although it's difficult to see why they brought him along, his useful suggestions at times of crisis notwithstanding. Glamour is provided by beautiful lady scientist Raquel Welch, who gets attacked by the antibodies (which is oddly appropriate). Arthur Kennedy is the chief scientist given to religious awe and philosophical musings (he makes observations along the lines of every heartbeat "separates man from eternity"). Donald Pleasence is the nervous, atheistic scientist who is continually trying to get the Proteus to give up the mission.
There is a clinical air to Fantastic Voyage that adds a little credibilty to the preposterous story. The lengthy, mostly silent, scene where the submarine is shrunk is fascinating to watch, the tension only broken by the claustrophobic Pleasence. When they finally get into the body, the old science versus nature conflict rears its head, with the crewmembers battling against natural defences and the perils of their anatomical surroundings.
The effects are almost psychedelic: the bloodstream looks like a lava lamp and the vessels and organs are coloured in muted pastel shades. Maybe a little more imagination could have made Fantastic Voyage exceptional; once you accept its one great idea you can second guess the film for the rest of the running time. For example, during the ear sequence the operating room has to be completely quiet, so what happens? Yeah, someone drops the scissors! Music by Leonard Rosenman. Watch for: James Brolin as a technician, and the great title sequence.