As the narrative unfolds, Julie Kohler (Jeanne Moreau) is initially found in a deeply distressed state, attempting to leap from an upstairs window until her mother, Luce Fabiole, intervenes. Clad in black and clearly in mourning, Julie presents a startling contrast in her next appearance, where she dons white and embarks on a quest to locate a man named Bliss (Claude Rich). Bliss, a notorious womanizer, is preparing for his wedding with an extravagant party when Julie, with her aloof charm, captivates him. In a shocking moment on the balcony of Bliss's high-rise apartment, she introduces herself before pushing him to his death.
Her merciless spree continues as she targets Coral (Michel Bouquet), a lonesome bachelor. Luring him to a concert, they fix a meeting for the following evening, during which Julie concocts a deadly plan. She buys a bottle of arak, lacing it with poison, and when Coral collapses after drinking, she reveals her identity. In an echoing flashback, a wedding procession is interrupted by a gunshot, revealing her tragic past as a widowed bride.
Julie's next target is Morane (Michel Lonsdale), an aspiring politician. She ingratiates herself with his family, posing as a teacher named Miss Becker. After establishing a connection with his young son, she orchestrates a scenario to isolate Morane. When he assists her in searching for a lost ring, she traps him in a closet, revealing her true identity once more. With desperate pleas for his life, Morane echoes the past sins of her other victims. Another haunting flashback conveys how her husband was murdered in a reckless accident involving Delvaux ([Daniel Boulanger]), another member of the hunting group that includes Bliss, Coral, and Morane.
Julie methodically eliminates Morane, suffocating him inside the closet with duct tape, leaving a haunting trace of her vengeance. Next, she seeks out Fergus ([Charles Denner]), the last of the men responsible for the tragic shooting. Under the guise of modeling for him as the huntress Diana, she ultimately delivers the lethal blow by shooting him in the back with an arrow, thereafter defacing his mural that captures her image.
Visiting Fergus' funeral, Julie ultimately surrenders to her fate, accepting arrest while embodying an air of calm. In prison, she begins working in the kitchen, hiding a knife amid the meal cart as it passes through the women's wing. As the cart maneuvers out of view, a man's scream echoes through the halls, a grim reminder of her relentless quest for revenge that transcends the walls of secrecy and sorrow she has built around her life.
