It's said that love can change a man, but one woman finds herself wondering just how powerful love might be in this comedy. Cora Dulz (Corinna Harfouch) is a psychiatrist who begins working with Stanislaus Nagy (Til Schweiger), a good looking but mysterious man who is obsessed with the late operatic diva Maria Callas -- and claims to have been her mentor during the height of her career. Not surprisingly, Nagy admits he has a hard time separating truth from fiction, but for reasons even Dulz finds hard, she finds herself fascinated with her new patient, to the extent of following Nagy after appointments and pursuing a romance with him. As things look to become more serious between Nagy and Dulz, he decides to make a little confession to her -- he wasn't really Callas' mentor. Instead, Nagy announces, he is actually Satan himself, and Callas was the result of a project in which he attempted to create the perfect woman. Nagy's relationship with Callas was a failure, however, and he's decided he wants to give up his career as the Lord of Darkness and instead live out his days as a mortal man. In order to do that, Nagy would need to find a mortal woman willing to take his hand -- would Dulz be at all interested?