It all starts quite peacefully. A couple in love lies in a forest clearing and dreams of a life where there are no compromises. But the paths of the lovers separate on their journey home. She gets into a red sports car, he takes the streetcar. She, that's Ruth Halbfass (Senta Berger), spoiled wife of an industrialist. He, the lover (Helmut Griem), is an art teacher at the public high school. The city is located in the Rhine-Main area, and in nearby Frankfurt, there is a so-called "underworld", where men can be found "who will do anything for money": Killers. "When a woman gets into gear, nothing can stop her", says Ruth Halbfass to her husband (Peter Ehrlich). The industrialist laughs about this "nonsense", yet while he is listening to old Richard Tauber songs, blaring from the hi-fi while he is dabbling in his swimming pool, a previously seemingly uninvolved young woman suddenly grabs an old shotgun?