Continuation of the successful series about Dr. Johanna Lohmann: The wedding bells are finally ringing and the whole of Großraming is excited to see whether Dr. Johanna Lohmann, after several attempts, will finally say yes to her fiancé, the veterinarian Laurenz Hofer. Johanna's son Max and his new friend Bastian, an orphan who the doctor has taken in, are also looking forward to the celebration. By chance, Johanna comes across a clue as to who Bastian's father might be: Daniel Winterberg, a horse breeder from a neighboring village. Winterberg denies paternity, but shows Johanna that he is very interested in her. This encounter also triggers feelings in Johanna. But Johanna has no time to ponder: Laurenz has diagnosed fatal pesticide poisoning in a dead deer. One of Johanna's patients, in turn, has inexplicable chemical burns on her arms. Everything points to illegal disposal of pesticides in a nearby pond. When Bastian goes into the pond despite the ban, he suffers a life-threatening allergic shock. Can Johanna save the boy? Will Bastian continue to have to grow up fatherless? And will Johanna finally marry Laurenz?