It's summertime, and that means summer camp! Tina and Bibi are attending the camp as well as a number of students from an international partner school. The highlight will be a “Geocaching” competition, a modern day treasure hunt between different teams.But one of the boys, Urs, stirs up trouble and and creates a rivalry between the girls and boys, and now even Tina's friend Alex wants to be on the boys' team rather than with his friends Bibi and Tina. Their team is instead joined by Francois a charming student from France.Urs and his team are pulling out all the stops in order to beat the girls and when Urs provokes and insults Bibi harshly she casts a spell on him, transforming him into the weirdest sort of bloke. But her powers are suddenly gone – and Urs is left with a giant head. Bibi is devastated: what's a witch who can't perform magic? Bibi and Tina try and get to the bottom of it, and are eventually pressed for time when there's a huge forest fire and her magical powers are the only thing that can prevent a catastrophe…