Maddie, learned as a child to get what she wanted- pleasure, pretty things, status, and the money with which to buy these. A pretty, precocious child, she had the charm and the intelligence to manipulate people. In 1650 she persuaded her father to arrange for her the marriage she wanted with Antoine Gobelin, Marquis de Brinvilliers, a rich nobleman of the family which owned the famous Gobelin tapestry works.
The marriage was a step up in the world for Marie-Madeleine: now in high society, she learned to spend money fast for the pleasures she wanted. She gambled for high stakes, and took lovers: her husband, who had his own mistress, did not object.
In 1659 her husband introduced her to a young Gascon adventurer, his friend the Chevalier de Sainte Croix. They quickly became lovers- openly and scandalously so. In 1663 her father, who hated scandal, used his official connections to get a “lettre de cachet,” an order for the arrest and confinement of Sainte Croix. These were readily available to persons in positions of influence, and were often used to deal with family scandals. After his arrest Sainte Croix was imprisoned in the Bastille for six weeks. There he shared a cell with Exili, a well-known Italian prisoner. Exili was used by statesmen for a period as part their policy, but at the moment the government thought him to dangerous to be at large. In their enforced intimacy, Exili and Sainte Croix became friendly: apparently Exili told Sainte Croix many of his secrets, and suggested to him that a man could make a good living by arranging the removal of unwanted people.
Sainte Croix had already dabbled with alchemy, his period’s ancestor of chemistry. When he was released, he set up a laboratory and began working seriously with poisons. Marie-Madeleine dropped the affair with her childrens’ tutor which she had begun to amuse herself with while Sainte Croix was absent, and followed her lovers new interest. They decided to prevent further paternal interference with their lives by poisoning Papa d’Aubray, a step which would also provide Marie-Madeleine with money to pay her debts.
But before undertaking a murder where their motive would be so apparent, the two decided to experiment with the effects of poison. Marie-Madeleine began to visit the Paris charity hospital, the Hotel-Dieu; she began bringing delicacies from her own kitchen to some patients, her “special children,” as she called them. Some died rapidly, some slowly: at length she was satisfied that she understood her poisons.
In 1666, her father fell ill. Marie-Madeleine was summoned, and went to help nurse him. Despite her devoted care, he became worse and worse. After twenty-seven to thirty doses of poison he died, thanking his daughter for her care with his last breath. the sudden legacy reduced her debts, but half of her inheritance went to Sainte Croix; she also resented that three-quarters of her estate went to her sister and her two brothers, when she had done all the work.
By now she seems to have become intoxicated with the sense of power she felt. Just to test the effects of the poison, she gave some to her maid, and to her own daughter (she disliked her anyway). They survived, since she was also testing her antidote.
Sainte Croix, alarmed by her recklessness, took away her poisons, but agreed to accept her as a client for his thriving poison business: he would arrange the deaths of her two brothers, who lived together, and Marie-Madeleine would inherit another nice chunk of money. Her part was to persuade her brothers to hire a servant, La Chaussee. They did not know that Sainte Croix had trained the man as a poisoner. Soon after her entered the d’Aubray household, the brothers fell ill: they vomited, their insides burned. La Chaussee nursed them devotedly, night and day, but they got worse. Both died: they left La Chaussee legacies, to thank him for his care.
Marie-Madeleine’s financial problems were solved, but only temporarily. Her extravagance outran all expenses. And she had other problems: La Chaussee blackmailed her into sleeping with him, and she quarreled with Sainte Croix, who tried to poison her. Recognizing the symptoms, she took the antidote. His business expanded to the point where discovery was inevitable before long.
Sainte Croix escaped discovery by dying in his laboratory in 1672, apparently poisoned by something he was making. When the police examined his laboratory, they found various poisons labelled as belonging to Madame de Brinvilliers. La Chaussee broke under torture, and told everything he knew.
But Marie-Madeleine had fled when he was arrested. She had taken refuge in a convent in the independent state of Liege. When Louis XIV’s army occupied Liege, she was lured out of her convent and arrested. Enraged at having been tricked, she tried to kill herself by biting a piece from her wineglass and swallowing it. When this failed, she tried to seduce the soldier of her guard.
After her trial, she was condemned to be taken in a dung cart to the place of execution, where she would be beheaded, and her body would be burnt. This was actually a merciful sentence during those times. The dung cart annoyed her: it offended her pride. The mob howled with rage as she was carted to the scaffold. She spent an hour kneeling there with her head on the block, while the executioner cut her long hair to prepare her for his stroke. The priest comforted her while she waited. At sunset the executioner removed her head with one stroke of his long sword.