On November 15, 1993, François Bonin let himself into his mother's house at 19 rue Edgar-Quinet in Thiais, as he did every evening, and found a young man going through a kitchen cupboard. The old woman had been taken ill, the stranger told him calmly; she was lying in a back room, with a little blood coming from her ear. Antoinette Bonin, seventy-six, did not answer when her son called her. When he turned back the man was gone. François saw the broken pane in the veranda door and the ransacked rooms, and his wife called for help, but his mother was dead, strangled. For a time the police suspected François himself, after his sister said he had always coveted the house. They lifted a palm print from the broken glass. The man in the kitchen was Claude Lastennet, and he had already killed once.
Lastennet was born in Brest on January 19, 1971, minutes after his twin brother Frédéric, the sons of a sailor who played no part in their lives. The boys were raised apart by aunts and uncles on the Crozon peninsula while their mother worked in Paris for the post office; she took them in two years later, and in 1983 the three went back to Finistère. In 1984 she married a man ten years younger, a violent drinker by Lastennet's account, and Claude, deeply attached to her, took it as a betrayal and left home in 1985 at fourteen. He trained in Quimper as a restaurant worker and a pastry cook, worked as a seasonal waiter, and by 1987 was a heavy hashish smoker and dealing in the hostel where he lived. Rejected for military service, he spent time in a psychiatric hospital in 1990 after his grandmother's death. In 1991 he waited tables at Chez Dumonet in Montparnasse, where older women customers gave him romantic appointments he accepted, until he was fired for refusing to serve people he disliked. In February 1993, staying with his brother in Paris, he tried to kill himself with Lexomil. That summer he stopped his medication and, penniless, began looking for old people on the street.
In August 1993 a neighbor on avenue du Président-Franklin-Roosevelt in Chevilly-Larue noticed a young man standing motionless on the pavement for two hours and asked what he wanted; he said he was looking for number 52, which was a park. He broke the glass in the back door of number 49, reached in for the key, and went in on Marcelle Cavilier, eighty-seven. When she refused to give him money they struggled, and he strangled her on her bed and took 12,000 francs. Her family found her on August 24, her face swollen from the beating; the killing itself is dated August 21 in one account and August 24 in another. The neighbor's description produced a composite sketch, but Lastennet had no police record. He paid his rent and debts with the money, and said later that he had not meant to kill her, but that getting away with it gave him an urge to kill again.
The day after Antoinette Bonin's death he strangled Raymonde Dolisy, seventy-two, whose name is also reported as Suzanne Fournier, in her home in Boulogne-Billancourt; the concierge found her three days later, alarmed by the post piling up at her door. On December 18 he strangled Augustine Royer, ninety-one, in her house in Bourg-la-Reine. It was after that killing that investigators saw the crime scenes lay along the same bus route, went back to François Bonin, and had him describe the burglar for a sketch. Two days later in Chevilly-Larue he forced his way in on Rosalie Czajka, eighty-two, a Polish immigrant, and demanded money at gunpoint. She gave him 500 francs; when he wanted more and threatened to kill her, she fought and screamed, a neighbor came, and he fled, dropping his cap. On January 8, 1994, he strangled Violette de Ferluc, ninety-two, in her third-floor apartment on avenue de Versailles in Thiais, tore out the telephone wires and ransacked the place; her son Gérard found her the next day when he brought her food.
On January 11, 1994, a young man from the same hostel, Arnaud Bossu, went to the police. Lastennet had asked him how to use a credit card he had stolen from an old woman he had killed, then, seeing his friend's disgust, said he was joking; Bossu read about Violette de Ferluc in the paper and knew he was not. The next day officers found Lastennet asleep in bed. He did not resist and admitted everything at once, and in his room they found the stolen card, jewelry, a beret and a radio. In custody he explained that he had picked his victims for details that caught his eye; he chose Raymonde Dolisy, he said, because of her big glasses.
His trial opened in October 1997 at the cour d'assises in Créteil, with Pierre-Olivier Sur defending him. Lastennet spoke of his crimes in the third person, said he had "dealt out death to become immortal, like Satan," and described dipping his right little finger in the blood that came from his victims' ears or noses, because blood excited him; he said he had been inspired by stories of vampires and Lucifer. On October 22, 1997, he was convicted on all counts and sentenced to life imprisonment with a security period of eighteen years, which made him eligible to apply for parole from January 2012. He said in prison that psychotherapy had helped him find himself again. He was never released, and he died at the Poitiers-Vivonne penitentiary center on December 19, 2023, at fifty-two.