[2] The beautiful paradise island Melonia is inhabited by the sorcerer Prospero with his daughter Miranda, the albatross Ariel, the good-natured vegetable-faced gardener Caliban and William the dog-nosed poet.

Once as green and flourishing as Melonia, Plutonia is now perceived as hell on earth, where children are forced to, under slave conditions, build weapons and tools of war, which Slug and Slagg believe is the way of the future.

The movie begins with one of the child slaves, a boy named Ferdinand, escaping from Plutonia in a box, and ends up on Melonia, where Miranda and Prospero nurse him back to health.

Eventually, Miranda helps the children escape by transforming them into birds and transporting them into an old theater, where William the poet is making a less than successful attempt at staging Shakespeare's The Tempest.

They then attempt to destroy Caliban using the great drill, but he easily lifts it off the ground and plunges it into the floor, causing the island to sink to the bottom of the ocean in a gigantic maelstrom.

The most negative review came from Variety, where Keith Keller wrote: "The Voyage to Melonia by Per Åhlin, Sweden's past master of animated films, probably has aimed over everybody's head with this go at The Tempest.