And as if that wasn't enough, he discovers that Olga's kiosk is in danger. So he has to choose – and make decisions...
A detective series for young readers, featuring a nine-year-old boy hero who has nothing to envy from the heroes of classic detective novels.
The series was awarded the Hansjorg-Martin-Preis in 2006, the most important German award for authors of children's and young adult detective books. It has been translated into 14 languages and has sold over 850,000 copies.
Book series number: 14