Quite an assembly of talent is ultimately wasted in this near-pointless look at a mental patient (that guy from the TV remake of Jason and the Argonauts) who thinks he's Hitler. A bunch of his fellow patients seem to think they're members of his staff, too. Essentially this is a re-imagining of Marat/Sade, adding in a head shrink (that guy from one of the Star Trek shows) who may be crazy too. Hitler's psychosis (the real Hitler, I mean) has been examined with substantially more depth and to a more powerful effect numerous times before.
Disney's first PG-rated film was pioneering for its time (integrating special effects better than any film before it), but it suffers pretty badly today. Maximilian Schell steals the show as a slightly crazed spaceship captain obsessed with black holes (the film plays out with everyone parked next to one... waiting for something). Anthony Perkins and Robert Forster lend an air of respectability to the rest of the movie, which unfortunately spends way too long on the cute little robot exploring Schell's ship with his yokel-bot friend (voiced by Slim Pickens).