 Kasperl and Seppel go out to catch Hotzenplotz as they assume that he intends new crimes.On their way to the den of robbers they build a trap by binding a sand bag on a tree and stretching the end of the rope over the ground, so that the sandbag falls down, when someone touches the rope on the ground.When Seppel tries their trap, it works perfectly and the sandbag falls on his head, so that he now lies unconscious on the ground.