Stefan Suttner's dog school is now so popular that the animal psychologist has to expand. But because of his ambitious plans, he comes into conflict again with his former friend, Mayor Wegerer, who is after the same piece of building land. When the owner let it be known that she would rather sell to Suttner, Wegerer didn't shy away from defamation in order to damage the reputation of the "dog whisperer": The rumor spread like wildfire in the village that Suttner had knocked Wegerer down in the argument and that's it The mayor refrained from reporting the case with generosity. The villagers quickly agree: you can't trust an animal like that. Suttner's reputation is ruined, all dog owners pick up their four-legged friends again. The dog school is threatened with the end. Only the sympathetic architect Julia Henschel doesn't give a damn about rumours. Stefan's assistant Xaver and the cosmopolitan hitchhiker Sari also support the animal psychologist. The situation comes to a head when Suttner's granddaughter Magdalena runs away and wants to climb a mountain all by herself. Only Suttner's faithful dog Dusty can save the girl. But as soon as this danger is over, new adversity threatens, because the mayor keeps trying to finally get his adversary out of the way.