Schilf plot
The physicists Sebastian and Oskar were best friends at university, an inseparable duo, one pragmatic and somewhat clumsy, the other ingenious and elegant. But after very fierce professional debates and after Sebastian is married and has a son, their relationship has cooled somewhat and the two rarely see each other anymore. But then Sebastian's son is kidnapped. The boy will not be released until Sebastian commits a murder; this is communicated to him anonymously. Sebastian desperately seeks help from his old friend.