The three friends Kim, Marie and Franzi solve exciting and mysterious detective cases as they go about their everyday lives as teenagers.

The three friends Kim, Marie and Franzi solve exciting and puzzling detective cases while going about their everyday lives as teenagers. Her cases range from fraud to theft to extortion and also cover issues such as cyberbullying and social justice. But there is also a big mystery waiting for the three junior detectives, which covers all cases and which has to be solved.