He is a spacemouse - the Geronimo Stilton of a parallel universe. He is captain of the spaceship MouseStar1. While flying through the cosmos, he visits distant planets and meet crazy aliens. His adventures are out of this world. -- Alien Escape -- Geronimo Stiltonix's spaceship is in danger of exploding. The only solution is to replace the engine's batteries by tracking down a rare element. When a group of mysterious aliens claim they can help, Geronimo is relieved. But are the aliens as friendly as they seem?