Bibi Blocksberg has spent far too much time on wizardry - and far too little on her studies. Since her math notes are abysmal, she is forced to spend summer vacation in the all-work-no-play boarding school of Altenberg Castle. The school principal is an oddball who is trying to solve the mystery of Altenberg, and Bibi's roommate Carina, a Britney Spears clone, is a total pain. Luckily, Bibi soon makes friends with her classmate Elea, who has been in a wheelchair since an accident. Of course, Bibi wouldn't be Bibi if she didn't try to help Elea walk again - even though her witch's codex expressly forbids her to intervene in human lives. But when she hears the tale of a miraculous owl powder, she sets out to find some in the caves of Altenberg. But someone else also knows about the magical powers of the blue powder: Bibi's archenemy Rabia von Katzenstein. In a dramatic escape, the wicked witch flees from the Dread-Marsh, where she was serving a five year sentence with her cat Maribor. Silently, maliciously, she sneaks up on the Blocksbergs, the family she hates with a passion...