It's a new semester at the world's top reform school, MUNCHEM ACADEMYThe snow is melting, the roof is leaking, and Mattie Larimore's father is now in charge. Mattie is worried, though. Mr. Larimore is taking the whole "let's help Headmaster Rooney get back on his feet" thing seriously, and he's whispering all sorts of suggestions to the highly suggestible Rooney. Then there's the matter of the school's weather. It's getting . . . strange. Mini-tornados sweep up out of nowhere. Rain pours inside. And there was that snowstorm-that yellow snowstorm.Speaking of strange, Delia Dane-Matoe's future archemesis-has just arrived at Munchem Academy. She seems to know a lot about Mattie and Munchem. Too much. But how? And . . . why?Once Mattie, Caroline, and Eliot figure out the truth behing the weird weather and Delia Dane, they need to act. Fast. There's only one thing to do: save the world-again. It's a tall order for a short kid,. But Mattie has a plan. . . .