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Authorities were skeptical of the letter’s allegations. Still, they recalled the public heartbreak of 25 years prior, when the Monniers’ daughter Blanche vanished without a trace. Blanche was known as a “joyous and playful” woman with a “wealth of beautiful hair and big, brilliant eyes.” Perhaps the letter was a twisted hoax—then again, what if it was true? Police decided to investigate.

Photo Credit: Altered Dimensions

Related: Behind Closed Doors: The Secret Life of the Knorr Family The door was locked when authorities arrived at 21 rue de la Visitation. When no one answered, they forced it open—and were hit with a wretched smell. They followed the stench upstairs to the attic. When they entered the room, they found a casement window covered by heavy curtains and coated in a layer of dust. Police could not open the shutters until they removed the hinges. And when daylight finally spilled into the musty chamber, a shocking sight came into focus. In the back corner, covered by a filthy blanket, was a skeletal, but still living Blanche Monnier. She was completely naked and lying on a rotten straw mattress, which had been soaked through by urine, feces. Fragments of meat, vegetables, fish, and bread formed a foul crust around her body. Now 49 years old, Blanche had withered down to 55 pounds.

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Through bouts of gagging, police wrapped Blanche in a blanket and rushed her to Hôtel-Dieu Hospital in Paris. Madame Louise, meanwhile, was discovered sitting calmly in the living room of her home, wearing a dressing gown decorated with black and white squares. Son Marcel was found in an adjacent room. Police sat down the pair and began their questioning. And it was then that the disturbing tale of Blanche Monnier came to light. When she was approximately 25 years old, Blanche had fallen for an older man—an attorney with few prospects and little wealth to his name. Rumors that the relationship produced an illegitimate child were abundant, and Madame Louise forbade Blanche from seeing the man. Blanche refused, at which point her mother begged her daughter to end to the affair. Blanche once more refused. Realizing that she would never persuade Blanche away from the penniless lawyer, Madame Louise hatched a plan with her son to force the change she desired. Related: 6 Must-Read Award-Winning Horror Books One evening, Madame Louise lured Blanche into an upstairs room and locked her inside. She told her daughter that the door would remain locked until Blanche agreed to break off the courtship. Madame Louise felt she had found the perfect solution to her problem. Certainly, Blanche would relent. But Blanche did not relent. And so, Madame Louise kept her daughter prisoner, feeding her scraps and ignoring the growing number of rats that congregated in the attic to feed on Blanche’s vomited food. As Blanche withered away, her lawyer lover died in 1885.

Photo Credit: Altered Dimensions

Madame Louise was arrested on the evening of the Blanche’s rescue. She was soon transferred to the prison infirmary when it was discovered that she suffered from heart problems. Fifteen days later, she was dead. Accused of being an accomplice, Marcel stood trial alone; the proceedings began in October 1901. He claimed that his sister Blanche was insane, and that she had not been restricted at all, but rather chose to stay in the room as an act of defiance. Court testimony contradicted Marcel’s defense. Several witnesses claimed that a woman, presumably Blanche, could be heard screaming from an upstairs room in the house. One witness professed to hearing specific words being shouted: “What have I done to be locked up? I don’t deserve this horrible torture. God must not exist then, to let his creatures suffer in this way? And no one to come to my rescue!” Related: Murder in the Red Barn: the Killing of Maria Marten Four days after the trial began, Marcel was found guilty and sentenced to 15 months in prison. Outside in the Palace Square, a waiting crowd voiced their approval of the verdict. But in mid-November, Marcel appealed the decision—and won. The court found that he had never acted violently towards his sister and acquitted him. To the public’s shock, he walked out a free man.

Photo Credit: Altered Dimensions