In the tenth volume of the bestselling series, the three Kaminski kids—Simon, Debora, and Raffi—can hardly believe their eyes: a police raid at their best friend Loko's house uncovers illegal goods. But Loko insists on his innocence. At the same time, Raffi spots a suspicious young man in the area. The kids and their collie follow his trail. However, they are interrupted by the Banfits: the youth gang gets the kids involved in a brawl and films it with a cellphone. Loko ends up injured in the hospital, and Simon is also hurt. To help, his girlfriend Antje arrives with her brother Mark. Together, they set out with renewed determination to investigate. Through the cellphone footage posted online by the perpetrators, they stumble upon a hot lead. But as they close in on the suspicious young man, things become increasingly dangerous.