For generations, the rats in the old junkyard have been telling each other the great legend about a moon made out of cheese and they want nothing more than to reach this inexhaustible treasure. One day, the little rat children discovered a comic in the junkyard that described the first landing on the moon, and thus the plan was born: Build a rocket and take over the cheese moon!

Fortunately, the junkyard has everything the rats need to build their rocket, and the other animals are willing to support this daring venture — at least if they're well paid. Of course, all the rats work together to achieve this mighty goal. However, each rat family competes to build the most rocket parts and to train the most rattronauts so they can feast on as much of the lunar cheese as possible.