Alexander wants so badly to win a painting competition at school so that he can impress Lotte, the girl he is in love with. After school, Alexander hangs out with his friends, including not only Lotte, but also his best friend and the class inventor Maulwurf. But when Maulwurf’s latest discovery, The Perlmutterfarbe, unexpectedly lands in Alexander’s hands, his life suddenly spins out of control. While the rest of the class is looking for the thief, Alexander keeps quiet as to the whereabouts of Maulwurf’s newest invention and tells a little white lie. Gruber, an unpopular boy, knows that Alexander has what the class is looking for, but covers for Alexander, using the situation to his own advantage: he claims that The Perlmutterfarbe has been stolen by the students from another class. In this way a war begins and Gruber becomes a frightening leader. Alexander gets tangled up in a web of lies and distances himself more and more from his friends.