A chimp in a spaceship goes off course into the far edges of the universe. Aliens enhance his intelligence to make him Captain Simian so he can defeat the evil Nebula, who wants to take over the universe.

Captain Simian hides the anti-force in a disco ball that destroys Nebula's powers and frees the universe.

The crew find a derelict ship, some crystals and an alien egg. The egg hatches with a quick-evolving alien that threatens the ship and crew. Splitzy uses the crystals to trap the alien and dump it into space.

The crew encounters an idyllic-looking, Earth-like planet run by a protege of Nebula, Rhesus 2, who has actually enslaved the planet. Captain Simian and his crew have to free them.

The Simians fight Rhesus 2 on the planet Medusa 4, where a device for anti-force can be found.