In the year 2312, a group of aliens auction off insignificant planets. and the winner of the auction for Sol 3 (Earth) is evil despot named Kress. He soon flies to "Sol 3" in what is the first contact with beings from another planet for those living there. Kress starts gathering humanoid slaves using his robot army to sell them to his evil counterparts.

Defending "Sol 3" against the new owner is the kindly Professor Maury and his ragtag band of human, one of which wears a Spider-Man t-shirt, and robot friends. Maury and his defenders set out to reclaim the planet from Kress and his cyborg army. Their plan is to destroy the metal of the alien ship, called Iridium (or etherium) after discovering its weakness.

After being defeated and retreating from the planet, Kress resells the planet at the space auction for a profit.