فصل 14

QUEEN OF POISONERS

Marie-Madeleine, the Marquise de Brinvilliers

Poison: forever the women’s weapon. It fits easily into the home. It’s subtle, secretive, tidy. Poison doesn’t leave blood on the floor or holes in the wall. Dropping a bit of colorless liquid into broth or wine is the simplest thing in the world. And who, historically, stays at home, boils the broth, and serves the wine? Women, of course.

Paris in the second half of the seventeenth century oozed with poison and the fear of poison and, by extension, the fear of women: the divineresses who dabbled in arsenic, spells, and abortions, and the rich young wives who frequented them. The court of the Sun King grew so paranoid that anyone with a stomachache panicked, sure that someone, somewhere, was trying to do them in. Major advancements in pharmacology, coupled with a very real fear of black magic, created the perfect atmosphere for a witch hunt, known today as the Affair of the Poisons. And many of those accused were female.

“How can . . . those who are so sensitive to the misfortunes of others . . . commit such a great crime?” wrote one bemused commentator, shocked at the number of lady poisoners who were swelling the city’s jails. “They are monsters. One must not suppose them like others, and they are sooner compared to the most evil men.” Sure, it was soothing in a weird way to imagine that these poisoners were more like men than girls, but it simply wasn’t true. These “monsters” were French noblewomen: they spent hours getting their hair done; they went dancing; they drank the iced champagne that was favored by the king. And the whole fatal affair was kicked off by a reckless little marquise named Marie-Madeleine.

La Brinvilliers

Marie-Madeleine d’Aubray, born in 1630, was the daughter of the civil lieutenant of Paris, a plum job that was both highly influential and very well paid. She had two younger brothers and a little sister who was probably not as cool as she was, given that the sister ended up in a convent and Marie—well, Marie was just one of those bold, lovely, spirited girls, you know? Proud, sensitive, quick-tempered. She had big blue eyes, chestnut hair, and a figure that was “not tall, but exceedingly well formed.” She was also smart. One historian who studied her letters reported that her spelling was flawless, “a rare thing with the ladies of her time,” and her handwriting was “remarkable—bold, firm, like a man’s.” Handwriting wasn’t the only precocious thing about Marie. Decades later, she would claim to have lost her virginity at the age of seven to her five-year-old brother—a statement she subsequently denied. But when Parisian gossips caught wind of the rumor, it only increased the atmosphere of taboo eroticism that swirled around Marie for most of her life.

As a young woman, Marie entered the fantastically libertine circles of high Parisian society that centered around Louis XIV’s amoral court. It was a dizzying world characterized by “utter heartlessness and a complete lack of moral fibre,” filled with scheming, bored nobles who liked to gamble for days without sleeping, spread malicious gossip about each other, engage in very public affairs, toss back glass after glass of iced champagne, and plot the downfall of their enemies.

Despite the corruption that ran through the court like a pulsing vein, there was definitely a sense in Parisian society that being a noble meant you were just better than other people. Nobles were convinced that being wealthy and powerful was positively correlated with being good—that being a noble lent their very character a certain nobility. Decades later, Marie’s lawyer would argue that she couldn’t possibly have committed any crimes because of her “advantages of quality, birth and fortune.” A noble could be a little bit naughty—late nights! lovers! too much gambling!—but aristocrats didn’t do anything that was actually criminal. That was simply unthinkable.

At twenty-one, Marie moved a little deeper into high society when she married the wealthy Antoine Gobelin, whose fortune came from the glamorous field of dye manufacturing. Gobelin’s income plus Marie’s dowry meant they were now a prosperous couple with considerable social cachet that they could fling around Paris. Even better, Gobelin’s land, called Brunvilliers, was eventually elevated to the status of a “marquisate,” which, along with a tweak in spelling, turned Marie into the marquise de Brinvilliers—or “La Brinvilliers,” if you were writing a gossipy letter about her.

Were they in love? Was anybody in love with their spouse back then? Toward the end of her life, Marie wrote of a deep affection for Gobelin, but shortly after their wedding they were both openly taking lovers. This was scandalous, and yet not at all unusual; in fact, a young, attractive, wealthy married woman was practically expected to have a paramour or two. Taking a lover didn’t get you ostracized in seventeenth-century France—it got you talked about. Besides, Gobelin was a weak man who didn’t seem to care what Marie did as long as he was free to indulge in his own lackluster affairs. Marie, on the other hand, “possessed superabundant vitality,” and it wasn’t long before she fell deeply in love with someone who was far better at meeting her needs than her husband was.

Unfortunately, she chose one of the bad guys. Her lover was a devilishly handsome army officer named Godin de Sainte-Croix—a ladies’ man with a serious dark side, a brilliant bastard who could wax eloquent on anything from theology to chemistry. For Marie, he was the “demon who brought about the storm and troubled the security of the family.” But Marie had always loved the storm. The two were soon the deliciously scandalized talk of the town.

While Marie’s husband was busily carrying on affairs of his own and didn’t care what she did with Sainte-Croix, her powerful father and brothers weren’t so easily distracted. They saw how openly Marie flaunted her affair, and they were absolutely humiliated by it. Other nobles may have tittered in delight at Marie’s erotic rampages, but for her male relatives, her behavior was neither aspirational nor a hilarious Parisian joke. It was utter ignominy.

Back then, if you were an important French person and someone was bringing shame on your family, you simply requested a little form for your nemesis’s arrest, signed by the king and known as a lettre de cachet. So one afternoon, as the two lovebirds rolled around Paris in their expensive carriage, they were intercepted by guards flashing a lettre de cachet from Marie’s father, and Sainte-Croix was promptly dragged off to the Bastille.

You can imagine the anger Marie felt at having her lover wrenched away by her father in public. On her way home, she “raged with the blind fury of a wild animal.” This was the beginning of everything for Marie. Later, she would note, chillingly, that “one should never annoy anybody; if Sainte-Croix had not been put in the Bastille perhaps nothing would have happened.” Good People

As Sainte-Croix whiled away six weeks in prison, he may have crossed paths with another prisoner there, a mysterious Italian poisoning expert named Edigio Exili. Serious poisoning hysteria hadn’t hit Paris yet, and poison was still thought to be the realm of the sneakier Italians. (A French pamphlet from the time claimed that in Italy, poison was “the surest and most common aid to relieving hatred and vengeance,” as though it were simply describing some sort of gastrointestinal medication.) Marie would eventually claim that Exili taught Sainte-Croix all about the enigmatic art of poisoning. Then she changed her story, saying that Sainte-Croix actually learned about poison from the Swiss chemist Christophe Glaser, celebrated scientist and apothecary to the king. Glaser was famous as much for his scholarship as for his wild recipes that called for ingredients like “the skull of a man dead of a violent death.” Of course, poisonous powders were available at any apothecary, so Marie could have picked up a vial of arsenic or antimony anytime she wanted. But these origin stories speak of the lovers’ desire to link their crimes to something bigger than themselves. They didn’t want to be regular, humble poisoners. They wanted to be co-conspirators with the greats; they wanted their poisoning attempts elevated to the ranks of macabre art.

With Sainte-Croix in the Bastille, Marie had a lot of time to grow angrier and angrier about the temporary loss of her lover. But that wasn’t the only stressor on her plate—she also needed money. Her husband was terrible with his finances, there were gambling debts to deal with, and Sainte-Croix was an expensive boyfriend, blowing through her income as though it were his own. Needless to say, her father’s wealth was starting to look particularly appealing.

As soon as Sainte-Croix was released on May 2, 1663, he rented a laboratory and began telling people he was an alchemist, or at least really close to becoming one. Ever aware of his bad-boy reputation, he began to hint portentously that he was very, very near a big breakthrough. But he also began doing something far more sinister—experimenting with poisons.

Poisoning made sense to the lovers. They needed money, they were furious at Marie’s dad, and if they hit upon the right formula, it would look like her father died of gout, stomach troubles, or a really terrible fever. In order to perfect their formula, Marie decided to test it on the patients of Hôtel Dieu, the famous public hospital next to Notre Dame. There, she wandered among the sick, distributing poisoned jams and sweets to her favorites, and weeping inconsolably when they inevitably died.

“Who would have dreamt that a woman brought up in a respectable family . . . would have made an amusement of going to the hospitals to poison the patients?” wrote Nicolas de la Reynie, the chief of police at the time. Marie looked like a good noblewoman, with her big eyes and pretty figure; she acted like a good noblewoman, deigning to stroke the fevered brows of dying beggars. It was hard for authorities like la Reynie to reconcile all this surface-level kindness and nobility with the fact that Marie wasn’t actually good at all. (Even when Marie should have been keeping house like a proper wife, she instead brought the evil home. She experimented on one of her servant girls by feeding her a one-two punch of poisoned gooseberries and poisoned ham, which gave the poor servant a terrible burning sensation in her stomach and three years of poor health.) When the lovers became confident their poisons were undetectable and highly effective, they moved in on Marie’s father. Marie planted a servant in his household who began dosing him with arsenic. The year was 1666. It was time for Daddy to die.

“Poisonous Waters”

Over the next eight months, Marie watched her father slip further and further away. After her servant had given him enough poison to destroy his health, Marie joined her ailing dad at his country estate and took over the dreadful process, dropping arsenic into his food and drink. His agonizingly slow death didn’t move her; she dosed him with poison almost thirty separate times. When her older brother came to check in on their father, he wrote to his boss in shock: “I have found him in the condition that was told me, almost beyond any hope of recovering his health . . . in such extreme peril.” After months of vomiting, tremendous stomach pain, and a burning sensation throughout his insides, Monsieur d’Aubray died on September 10, 1666. The cause of death, according to his doctors? Gout.

The inheritance money was divided among the four d’Aubray siblings, and Marie and Sainte-Croix quickly burned through their share of it. By 1670, they were back where they started: desperate for money, chased by creditors, and resentful of anyone who’d ever opposed their love.

Marie’s brothers lived together, conveniently enough, but the older one was married to a woman who hated Marie. This meant that Marie wasn’t welcome in the kitchen, and so she was unable to “access” (wink) the tarts, the savory pies, and the wine. So she planted another servant. He went by the name La Chausée, and he was perfect for the job: he’d already worked for Sainte-Croix, he had a criminal record, and, like Marie, he was creepily patient when it came to watching people die. La Chausée went to work right away with a selection of “poisonous waters” (there was a reddish one and a clear one), spiking various drinks and an elaborate meat pie that both brothers ate with gusto. Soon enough, the men were complaining of burning sensations in their stomachs.

The death of Marie’s brothers was another excruciatingly drawn-out process. We’re talking months of suffering: vomiting, inability to eat, cramps, loss of eyesight, bloody stools, swelling, weight loss, and a constant fire gnawing away at their stomachs. Their bodies grew so “stinking and infected” that it was hard to be in the room with them. It’s difficult to imagine the type of sister who could watch her siblings die so slowly, in such agony, but that was the thing about Marie. She was furious. The “violent Passions” that saturated her life included not just lust and greed, but a burning desire for revenge. And her brothers, along with her father, made up the patriarchal cage she was constantly rattling against. They sent her off to a weak, boring husband and then punished her when she tried to escape him. They insisted that she behave not just for her own sake, but for the sake of their reputations. She answered them with terrible vengeance.

Her older brother passed away in June, while the younger one lived until September. Autopsies for both brothers revealed the same wrecked insides: the stomach and liver were blackened and gangrenous, and the intestines were literally falling apart. After the younger brother’s death, doctors began to suspect the two had been poisoned, but they didn’t press the matter. No one had any idea who could have committed the crime, since La Chausée masqueraded so well as a faithful servant and Marie made sure she was miles away when each one died. La Chausée even received a tidy bonus of one hundred crowns for his faithful service.

Now that all her closest male relatives were dead, Marie began plotting the murder of her sister, a devout single gal with a large fortune. She also wanted to poison her sister-in-law, who had just inherited some of the d’Aubray wealth, a fact that irritated Marie. Plus, she’d been toying with the idea of poisoning her husband and marrying Sainte-Croix—though Sainte-Croix didn’t seem very excited about that idea. One of the great gossips of the time, Madame de Sévigné, noted that while Marie kept giving her husband poison, Sainte-Croix—“not anxious to have so evil a woman as his wife”—kept slipping the poor man remedies. The result? “Shuttlecocked about like this five or six times, now poisoned, now unpoisoned, he still remained alive.” Needless to say, Sainte-Croix and Marie were no longer in their honeymoon period. A furious Marie even wrote him a letter claiming that she didn’t want to live anymore and so had just poisoned herself with his formula, which she’d bought from him at such a high price. In fact, Marie had taken another lover just after her brothers died. This man would be just as destructive to her as Sainte-Croix was, but in a different way; while Sainte-Croix encouraged her crimes, this lover would turn against her because of them. But for now, Marie had no idea that he’d ever betray her. All she knew was that this new man was kind, young, and good.

Sundry Curious Secrets

Jean-Baptiste Briancourt was hired as a tutor for Marie’s children in the fall of 1670 and became her lover shortly afterward. Like her husband, Briancourt was a weak, cowardly man, but he must have been an appealing foil for Sainte-Croix, since Marie was feeling especially vulnerable about her relationship with Sainte-Croix at the time (thus the marriage attempts and the threat of suicide). Where Sainte-Croix was unscrupulous and unafraid, Briancourt was moral and wary. He was completely infatuated by the marquise, but also terrified of her; she talked incessantly of poison and told him all about her crimes. He could see how cruel she was to her daughter, and suspected Marie was trying to poison the girl.

Eventually, Briancourt began to wonder if the marquise was plotting to kill him, too. His worst fears were confirmed when Marie asked him to come to her bed at midnight. When Briancourt happened to pass by her room a bit earlier than planned, he saw Marie hiding Sainte-Croix in her closet. The resulting scene was practically vaudevillian: Briancourt showed up at midnight, hurt and silent; Marie tried to tempt him into bed; Briancourt suddenly lunged toward the closet; Marie flung herself onto Briancourt’s back, shrieking, to prevent him from opening the door; Briancourt opened it anyway, came face-to-face with a creeping Sainte-Croix, and screamed, “Ah, villain, you have come to stick a knife into me!” At that, Sainte-Croix scrambled out of there as fast as he could, and Marie rolled on the floor screaming and crying and threatening to poison herself. Eventually, Briancourt calmed her down by promising to forgive her, all the while hatching a plan to flee in the morning.

Marie was cracking. She may have been cool about murdering relatives, but the torrid relationship with Sainte-Croix was starting to fray her. She was beginning to realize that this man had, in a way, stolen her entire life. She had given him her wealth and her time and her love; she had bound herself to him with the most horrible secrets. In turn, he had taken and taken from her without remorse and, now that things were getting messy, he seemed to be pulling away. Finally, in his last great betrayal of Marie, Sainte-Croix died before his crimes were ever discovered, leaving her to take the fall for both of them.

Legend says that on July 30, 1672, Sainte-Croix was whipping up poisons in his secret laboratory, wearing a glass mask to avoid breathing the dangerous fumes. As he bent over the fire to stir some devilish pot, his mask shattered, and Sainte-Croix was immediately killed by his own poison. His actual death wasn’t nearly so poetically just. He simply died after a long illness, with none of the authorities suspecting him to be a criminal. In fact, he died a good man in the eyes of the church: he was able to perform his final devotions and receive the last rites.

He was, however, disastrously in debt, and so the Paris courts sent over a commissary to put his affairs in order. (Ironically, the commissary came from the same building where Marie’s father used to work.) The man initially uncovered a mysterious scroll titled “My Confession,” but since Sainte-Croix wasn’t accused of anything at the time, he decided that the document was some sort of sacred declaration between a man and his God, not meant for public consumption. As such, he tossed it into the fire.

But the commissary also discovered a little box full of cryptic vials and powders, which turned out to be things like antimony, prepared vitriol, corrosive sublimate powder, and opium. Even stranger, the box came with a note saying that upon the event of Sainte-Croix’s death, the contents should be immediately given to the marquise de Brinvilliers. “All that it contains concerns her and belongs to her alone,” ran the note. “In case she dies before I do . . . burn it, and all that is in it.” There were also multiple papers and envelopes marked “to be burnt in case of death,” and one biographer reported that Sainte-Croix actually dared to label an envelope “Sundry Curious Secrets.” Unsurprisingly, the commissary turned the box over to the police.

The whole affair only grew more suspicious when Marie rushed over to the authorities late at night, demanding that the box of poiso—uh, “curious secrets”—be handed over to her. She should have played it cool, acting nostalgic for the effects of a deceased lover, but her “very eager and extraordinary manner of demanding it” immediately caused the authorities to become apprehensive. Instead of giving her the box, they decided to test its contents, and fed two of the most enigmatic liquids to a selection of animals, all of which died within hours.

When Marie’s sister-in-law heard about the mysterious box full of poisons, she went on a legal rampage, demanding vengeance for her husband’s murder. She lodged an accusation against La Chausée, who was dragged off to jail, and she told the authorities to snatch up the marquise de Brinvilliers immediately.

Marie fled the country.

Ordinary and Extraordinary Questions

While French authorities scoured the continent for the marquise, La Chausée went to trial. As a low-ranking member of society with a criminal record and an angry noblewoman on his case, he never stood a chance. He was found guilty before he had confessed a thing, based solely on “conjectures and strong presumptions.” On March 24, 1673, the judges sentenced him to be executed after undergoing torture: the “ordinary and extraordinary questions.” The questions were a form of water torture in which the victim’s nose was pinched shut, his body stretched backward over a trestle, and copious amounts of water forced down his throat—twice as much water for the extraordinary as for the ordinary. After groaning through the questions, La Chausée was then shoved into a horrific torture device called the brodequins: with his legs stuck between planks, wooden wedges were slowly hammered into the space between plank and leg, eventually crushing his calves. La Chausée refused to confess a thing during the torture, but once he was released from the brodequins, the truth came pouring out of him. (Apparently this was common with torture—the sheer relief of being free from the pain often brought about a veritable torrent of confession.) He was then tied to a wheel, beaten with iron bars, and left to bleed out in agony. An execution like this was known as being “broken on the wheel,” and brings to mind a sort of cross—one where the victim dies facing the sky.

For exactly three years and one day after La Chausée was sentenced to death, Marie avoided capture. She moved around Europe, surviving on small amounts of money sent by her sister—the same sister she had once planned to kill. When her sister died in 1675, Marie was left to survive as best she could and eventually rented a convent room in Liège, which was then an independent city-state full of French troops. This was a huge mistake. Word soon reached the Parisian authorities that the infamous La Brinvilliers was hiding out in a convent, and they descended on her.

As Marie was dragged back to Paris for trial, she tried to kill herself multiple times by attempting to swallow pins and mouthfuls of crushed glass. If she’d been the talk of the town during her halcyon days with Sainte-Croix, she was even more famous now. A rumor began to circulate that she had tried to impale herself by pushing a sharp stick between her legs. As a friend wrote to Madame de Sévigné, “She thrust a stick—guess where! Not in her eye, not in her mouth, not in her ear, not in her nose, and not Turkish fashion [anally]. Guess where!” La Brinvilliers had carried on a public affair for so many years that now even rumors of her suicide attempts framed her in a hypersexual light. But Marie was no longer the wild child of libertine Paris. At forty-six, she was a marked woman, and she was exhausted.

When Marie was arrested, a sheaf of papers had been discovered in her room—a written confession. Like her lover, Marie had been desperate to unburden her conscience. In the document, she indicts herself of “bizarre and monstrous crimes”: killing her father, murdering her brothers, letting La Chausée be broken on the wheel because of her crimes, attempting to poison one of her children, thinking about killing herself, burning down a barn, plotting to kill her sister, and trying to poison her husband. In fact, she more or less recants her whole life. “I accuse myself of having created general scandal,” she writes. “I accuse myself that I did not honor my father, and that I did not render to him the respect I owed him.” She confesses to having two children with Sainte-Croix and a third child with a cousin, to losing her virginity at age seven to a brother, and to committing incest “three times a week, perhaps three hundred times in all.” She also declares that, in giving herself to Sainte-Croix, she caused her own ruin.

Of course, in one fell swoop, Marie distracts us all from murder with her extreme claims of incest, which at least one historian has speculated could be code for childhood abuse. At the time, they merely fueled her reputation as a voraciously lustful woman. But upon reading her confession today, we’re confronted with a portrait of a desperate, desolate woman, saturated with regret and exhaustive in her self-immolation: she moves from not honoring her father to killing him, from killing her brothers to sleeping with them, from creating “general scandal” to causing the torture and death of an unfortunate petty criminal. In court, she denied the whole thing, claiming she was out of her mind when she wrote it: feverish, confused, alone in a foreign country.

Since she was a woman of high social standing, the court needed substantial evidence to prove her guilt—and the incriminating “confession” wasn’t enough. Many witnesses took the stand against her, and one theme that emerged was that La Brinvilliers had been obsessed with poison. One woman testified that Marie had gotten drunk at a dinner party and flaunted Sainte-Croix’s box of poisons, laughing, “Here is vengeance on one’s enemies; this box is small, but is full of inheritances!” Another man heard that Marie told Briancourt (ah, the Parisian gossip machine!) that there were “ways to make away with people that displeased her.” Still, none of these testimonies were quite enough to convict her, until the court brought in the one person who knew all about her crimes: Briancourt himself.

Marie listened to her former lover testify against her for a total of eighteen hours. He told the court everything: how she and Sainte-Croix killed her father and brothers, how she asked him for help with the murder of her sister and sister-in-law, how she plotted to murder him with Sainte-Croix in the closet. Marie listened with frightening hauteur, responding that Briancourt was a drunkard and a liar. When Briancourt began to weep on the witness stand, saying, “I warned you many a time, madam, about your disorders and your cruelty, and that your crimes would ruin you,” Marie called him a coward. The court was stunned by her eerie, unfeeling composure, but Briancourt’s testimony was exactly what they needed to convict her.

Marie really was a vision in the courtroom: calm, cold, proud. She denied everything, over and over, even as her life was “remorselessly dissected” in front of her. The horrible nature of her crimes made everyone else highly emotional—at one point, even the judges were crying—but Marie “kept her head proudly erect, and preserved undimmed the stony clearness of her blue eyes.” On July 16, 1676, the judges declared her guilty, and sentenced her to the ordinary and extraordinary questions, hoping she’d spill the names of any accomplices during the torture. After the questions, she would be beheaded. In a way, this sentence was merciful. They could have had her burned alive.

De Profundis

Marie was given a confessor, a Jesuit priest named Edmé Pirot, who was every bit as sensitive and empathetic as Marie was proud and cold. Pirot was such a delicate soul, in fact, that he claimed to faint at the sight of blood. The sight of Marie—who was by that point very thin, and of course very doomed—immediately tugged at his heart.

Like Briancourt before him, Pirot desperately wanted Marie to repent, and miraculously, Marie was now willing to do so. After spending some time with him, she declared that she was ready to make a full confession to the court. There, in front of everyone, she finally admitted that she’d killed her father and brothers. Perhaps she was hoping to avoid torture.

Unfortunately, she didn’t tell the court anything they didn’t already know; they were hoping for accomplices, dark secrets, important names. Poisoning paranoia had begun to creep through the city, and authorities were already panicking about the terrifying subtlety of these sorts of crimes. They feared that after Marie’s death, her poisons would somehow kill again. After all, in her written confession, she mentioned selling poison to another woman who wanted to kill her husband. Who knew where this web of feminine evil would spread next?

So the torture began. Marie was stripped naked and bent backward over a wooden trestle, with her ankles tied to the floor and her hands tied to the wall behind her. The torturer began to funnel water down her throat, and after she came up from each dose, coughing and gasping, she was questioned.

“My God! You are killing me!” she wept. “And I only spoke the truth.” More water was funneled down her throat. “You are killing me!” she cried again. The trestle was raised, her body stretched even farther, and the extraordinary question began. “O God, you tear me to pieces!” she screamed. “Lord, pardon me! Lord, have mercy upon me!” Her ankles and wrists began to bleed, and the water kept pouring down her throat, but still La Brinvilliers refused to confess any more than she already had, groaning that she would not tell a lie “that would destroy her soul.” After four and a half hours of torture, the men realized that if Marie carried any dark secrets with her, she was taking them to the grave. So they told her to prepare herself for death, and sent her back to her confessor.

Apparently the indignity and horror of the torture had awoken some of Marie’s old fire. She’d been humble and penitent in front of Pirot the night before, but now she was incensed at the humiliation she’d endured as well as the humiliation she was about to endure. She would have to do public penance on her way to the scaffold and then, after her death, her ashes would be scattered to the winds—an unthinkable ending for the haughty marquise. Pirot tried so hard to bring her back to a repentant state that he began to weep. Finally, after an hour of his pleading and tears, Marie began crying, too.

The execution of the scandalous La Brinvilliers was quite the happening event, and many Parisian nobles turned out to see her inglorious processional. A tiny, dirty tumbril arrived to carry her to the scaffold. On her way to the cart, Marie had to walk past a group of nobles who’d weaseled their way into the jail to catch a glimpse of the infamous woman, curious if she was still the same girl that they’d danced with, gambled with, and toasted with iced champagne. Now she was barefoot, wearing a coarse white shift with a noose slung symbolically around her neck.

The ride through Paris—with even more nobles gaping at her and everyone yelling that she deserved to die—was an incredibly demeaning ordeal for a woman of status. Pirot, watching her closely, saw her literally convulse with rage and humiliation: “Her face contracted, her brows were knitted, her eyes flashed, her mouth was distorted, and her whole aspect was embittered.” A sketch of this awful moment, immortalized by Charles Le Brun, hangs in the Louvre today. It’s a grim portrait of cyclical human brokenness—the killer on her way to be slaughtered.

The procession edged toward Notre Dame, where Marie was forced to get out of the cart to perform a public penance. She knelt, holding a lit torch, and proclaimed, “I confess that, wickedly and for revenge, I poisoned my father and my brothers, and attempted to poison my sister, to obtain possession of their goods, and I ask pardon of God, of the king, and of my country’s laws.” Later, Pirot wrote, “Some people say that she hesitated in saying her father’s name—but I noticed nothing of the sort.” On the scaffold, the executioner shaved Marie’s hair and ripped open her shirt to expose her neck and shoulders. Pirot whispered prayers in her ear to calm her, while the snarls of the crowd rose and fell around them like waves. The executioner covered her eyes, and she began to obediently repeat a prayer after Pirot, when a long sword flashed through the air. Marie fell silent.

Suddenly nauseated, Pirot assumed that the executioner had missed her head entirely, because though Marie was no longer speaking, she still knelt upright, with her head on her shoulders. Moments later, though, her head slid off her neck and her body fell forward. The executioner asked Pirot, “Was that not a good stroke?” and immediately drank a mouthful of wine. As Marie had requested, Pirot began to recite a de profundis, the Catholic prayer for the dead, over her bleeding body: Out of the depths I cry to You, O Lord.

“We Shall Breathe Her”

La Brinvilliers was dead, and Paris was terrified, scandalized, thrilled. “The affair of Mme de Brinvilliers is frightful, and it has been a long time since one heard talk of a woman as evil as she,” wrote one Parisian gossip to another. “The source of all her crimes was love.” Since Marie had made no secret of her sexual appetite, flaunting her affair with Sainte-Croix all around Paris, the narrative of the beautiful marquise poisoning for love was a natural one for her peers to latch onto.

Love and its close cousins, lust and obsession, have been identified as the “source” of female crimes since the beginning of time, in a host of archetypal ways: the jealous mistress, the spurned lover, the mad Ophelia, the brainwashed Manson girl. Love makes for a story that’s not just romantic, but pleasant. It’s a clean-burning fire, after all; love may destroy things, but at its core, love is supposed to be true and noble, kind of like how at their core, French nobles were assumed to be good. If the source of Marie’s crimes was love, it would seem to negate the worst part of her wickedness, or at least make it more socially acceptable. A good noblewoman was allowed to go a little bit crazy when it came to love, especially a noblewoman in love with a man like Sainte-Croix, who swaggered around boasting about his pseudosciences and attempting to transform base matter into gold.

Today, we can see that love wasn’t what drove the marquise to kill, despite what the gossips insisted. She loved, and was loved, and perhaps love led to her downfall, but she was also furious, vengeful, and fixated on her box of “inheritances.” (“One should never annoy anybody!”) But money was prosaic, and revenge was distasteful in a noblewoman, so the narrative of love was the one that stuck.

Even with its romantic allure, her story left Paris traumatized—and paranoid about the use of poison. If a lovely, wealthy woman could poison the men closest to her, then who wouldn’t poison? If nobility could turn evil, then who was safe?

“Well, it’s all over and done with, Brinvilliers is in the air,” wrote Madame de Sévigné to a friend. “Her poor little body was thrown after the execution into a very big fire and the ashes to the winds, so that we shall breathe her, and through the communication of the subtle spirits we shall develop some poisoning urge which will astonish us all . . . Never has such a crowd been seen, nor Paris so excited and attentive.” In fact, some of Paris was so attentive that they watched the burning of Marie’s body till the very end. They wanted to see where her ashes would land. The people who stood closest to the scaffold reported that her face was illuminated by a halo just before the beheading. Death had made her a saint, they said, and went searching through the cinders for bits of bone.