At a formal ceremony, the anthropologist Étienne Sembadel is honoring his longtime colleague Octave Clapoteau. A young veterinarian, Esther Bouloire, who had spoken with Sembadel at one of his lectures, steps forward and asks if they can dine together. What begins as a strange, almost desperate invitation soon spirals into a web of suspicion, family secrets, and deadly power plays.
Esther reveals a chilling claim: she believes her sister Genevieve was murdered and her body burned. The two academics, though wary, listen, but their skepticism is clear enough to push Esther to seek help elsewhere. They decide to place her in a mental health clinic to ensure she receives proper care. After her release, the trio—[Esther Bouloire], [Étienne Sembadel], and [Octave Clapoteau]—accompany the heavily medicated Esther as she drives toward her veterinary practice, then forcefully enters the office of her late father’s law business, and shows them the layout of her house and the house of her “evil” cousin, Muriel.
Esther proceeds to explain the Bouloire family’s tangled history: her father and his brother Leopold, who ran the Bouloire Brothers business, died in mysterious car accidents along with their wives. The enterprise is now controlled by the hunchbacked third brother, [Jocelyn Bouloire-Haussmann], who tells a story of his own while maintaining a carefully controlled public image. The two academics press for answers, and Esther urges them to meet Jocelyn, hoping he might confirm what she suspects.
Their next move is to confront the brother-in-law, but he comes across as a peculiar, sports-obsessed eccentric, hardly the profiling target Esther hopes for. Undeterred, the investigators press on and decide to seek Jocelyn out themselves. The encounter with Jocelyn reveals that Genevieve was fond of a Swiss lawyer named Bongrand; however, a trip to Geneva yields another dead end. Mr. Bongrand informs them that Genevieve might have known his son, Paul Bongrand Jr., who recently died in a climbing accident in the Dolomites. Soon after, the two academics are arrested by the police on suspicion of involvement in Bongrand Jr.’s death.
Back in France, the plot thickens as Homecourt appears seeking help from Muriel, only to encounter Esther instead. He confesses that three killers are hunting him because someone claimed that he had revealed the name Munoz to Sembadel and Clapoteau. He admits involvement in Munoz’s murder but refuses to disclose Genevieve’s whereabouts. Esther ejects Homecourt from the premises, and he is shot dead as he leaves through the gate.
Three days later, Jocelyn confronts Sembadel’s wife with a damning charge: Esther and her husband are responsible for Homecourt’s death. The revelations threaten to tear the small circle apart, and suspicion quickly shifts toward Esther herself. The pressure drives the pair to take drastic steps: they publish a comprehensive article in Left-Weekly detailing twelve murders tied to the Bouloire network, including Homecourt’s European killings and the fates of Esther’s aunts and uncles. In parallel, Esther presents journalists with documents found in her sister’s safe that incriminate 41 people, including three ministers, intensifying the political stakes of the case.
Tragedy continues to mount as Muriel is shot dead by three assassins while leaving the Bouloire-Haussmann offices. Esther teams up with Léon, Muriel’s husband, to rescue Sembadel and Clapoteau from their apartment, and the four attempt to flee the city. Léon, consumed by grief and danger, decides to return for his wife’s funeral but is fatally shot on his way home. The remaining trio—Esther, [Étienne Sembadel], and [Octave Clapoteau]—hurry toward a safer sanctuary, chasing a lead that takes them to the Countess Renata Palozzi’s chateau. Renata Palozzi somehow provides a path to safety, guiding them to Rome. Yet safety proves fragile: moments after escaping the immediate threat, Sembadel and Clapoteau are gunned down near the Vatican, leaving Esther to confront the last, intimate consequences of the conspiracy.
In the end, the two scholars meet their fate, but the film closes on a surreal, almost celestial note as they appear to celebrate their final moment together—dancing in Heaven—an eerie, poignant coda to a thriller built on secrecy, guilt, and the price of truth.
