Julien (Jacques Dutronc), a former concert pianist and ex-husband of Jeanne Kern (Isabelle Huppert), sets out to win her back by framing her new husband, Dr. Stephan Kern (Bruno Ganz), for murder. He blackmails Detective Keller (Christian Rist) into committing the crime, but ultimately shoots him dead instead, using Stephan's revolver and manipulating clues to incriminate the doctor. As tensions rise in their troubled household, Jeanne begins to unravel Julien's plot, while the police work to uncover the truth, releasing Stephan from custody just as Jeanne confronts Julien about his actions.