Mildew and Sponge don't think much of Maudlin Towers, the blackened, gloom-laden, gargoyle-infested monstrosity that is their school. But when a meteorite crash-lands in the school grounds, things become even stranger than they have ever been before! Not only do a group of schoolgirls and their teacher turn up needing somewhere to stay, but further investigation of the meteorite soon proves that it might be a spaceship. Could aliens be hiding in the school grounds somewhere? (You might have spotted them already!) Plus, has anyone noticed a giant eyeball floating about the place? Most importantly, can Mildew and Sponge save the day - and the school - once more?