Even at the very beginning of her life, it was clear that Margaretha Zelle would become someone extraordinary. From the early days of her childhood in northern Holland, she stood out: flamboyant, striking in appearance, bold, bright, and gifted in languages. One schoolmate compared her to an orchid among dandelions, contrasting her dark exotic looks with the fair skin and blond hair of most other Dutch children.

Born in 1876, she learned as a young girl that she could get what she wanted by pleasing men, starting with her doting father, Adam Zelle. Margaretha was her father’s overwhelming favorite, and he showered her with extravagant gifts. In 1889, however, Margaretha’s father abandoned the family and ran off with another woman. Her mother, Antje Zelle, died a couple years later, when Margaretha was a teen.

After her mother’s death, Margaretha—thoroughly spoiled and precociously sexual at age 14—was sent away to learn to be a teacher. At 16 she was expelled for having an affair with the married headmaster of the school. From there, she then moved to The Hague, a city full of colonial officials who had returned from service in the Dutch East Indies (modern-day Indonesia).

At 18, bored, miserable, and desperate for some kind of adventure, she answered a newspaper advertisement posted by one such official, Capt. Rudolf MacLeod. He was looking to meet, and marry, “a girl of pleasant character.” Marriage to such a man seemed the perfect path to a better life. Margaretha knew officers in the Indies lived in large houses with many servants. “I wanted to live like a butterfly in the sun,” she said in a later interview. They were engaged six days after meeting, and married in July 1895.

Marriage of Misery

Life did not turn out as the young woman expected, for MacLeod had little money, great debts, and lots of extramarital affairs. On the ship to the Dutch East Indies in 1897, with their baby son Norman-John, Margaretha discovered her husband had given her syphilis, a disease rampant among Dutch colonial soldiers. There was no known cure at that time, though treatment with toxic mercury compounds was believed, erroneously, to be a cure. Back in the Dutch colony, MacLeod continued his wild ways while Margaretha attracted attention from other men for her beauty and flirtatious manner, which infuriated her husband. She had a second child in 1898, a daughter named Louise Jeanne, but the marriage remained deeply troubled.

In 1899 MacLeod was promoted to garrison commander in another part of the Dutch East Indies and left his wife and family behind to find a house there. Both children fell ill, probably from congenital syphilis. When the family was reunited, MacLeod called the base doctor. Used to treating grown men, the doctor overdosed both children, who spewed up black vomit and writhed in agony. When their two-year-old son died, everyone on the base guessed why. This scandal led to MacLeod’s demotion and posting to a small, remote station.

The couple did not bother to disguise their mutual hatred. In 1902 they returned to the Netherlands and separated. A divorce would ensue: Although Margaretha initially won custody of her daughter, Louise Jeanne would be raised by her father.

Paris Sunrise

A profound and fateful transformation took place in the young Dutchwoman. Colored by her travels and sorrows in the Indies, Margaretha Zelle reinvented herself as something startling and new: an exotic dancer called Mata Hari. In 1905 Mata Hari—a Malay term for “sunrise” or the “eye of the day”—broke onto the social scene with a performance in the Musée Guimet, an Asian art museum in Paris. Invitations were issued to 600 of the capital’s wealthy elite. Mata Hari presented utterly novel dances in transparent, revealing costumes, a jeweled bra, and an extraordinary headpiece.

Under any other circumstances, she could have been arrested for indecency, but Margaretha Zelle had very carefully thought through her position. At each performance, she took the time to explain carefully that these were sacred temple dances from the Indies. Mata Hari was sensuous, beautiful, erotic, and emotional; she told tales of lust, jealousy, passion, and vengeance through her dancing, and the public lapped it up.

In an age when every rich and influential man wanted a beautiful mistress on his arm, Mata Hari was acknowledged as the most glamorous, fascinating, and desirable woman in Paris. She was seen with aristocrats, diplomats, financiers, top military officers, and wealthy businessmen, who kept her in furs, jewels, horses, silver, furniture, and chic accommodations simply for the pleasure of being in her company. For years, she danced in sold-out performances in nearly all the major European capitals.

As Mata Hari aged and her dancing career began to wind down, she was still in demand as a courtesan and enjoyed the company of rich and powerful men. The outbreak of World War I in 1914 did not alter her extravagance. She seemed not to grasp that ordinary people resented her ostentatious lifestyle while French families were doing without basics: coal, clothing, and foodstuffs. They were sending their fathers, husbands, brothers, and sons to be killed in the war while she continued to live in comfort and plenty.

Dancing Double Agent

Mata Hari continued to travel, which brought her to the attention of the counterespionage world. The fall of 1915 found her in The Hague, where the exotic dancer was paid a visit by Karl Kroemer, the honorary German consul of Amsterdam. He offered her 20,000 francs—equivalent to $61,000 in today’s currency—to spy for Germany. She accepted the funds, which she viewed as repayment for her furs, jewels, and money the Germans had seized when war broke out. Even so, she did not accept the job.

Returning by sea from the Netherlands to France in December that year, she and all of the passengers were questioned in Folkestone, a British port, by an intelligence officer. Nothing incriminating was found in a search of her person and luggage, but the officer noted: “[She] Speaks French, English, Italian, Dutch and probably German. Handsome, bold type of woman. Well and fashionably dressed.” His verdict on her? “Not above suspicion . . . most unsatisfactory . . . should be refused permission to return to the U.K.”

Having returned to Paris, she lived at the Grand Hotel, which had been largely spared the ravages of war. She was so used to men’s attentions that, for the first few days at least, she did not notice that she was being followed. Georges Ladoux, the head of the newly formed Deuxième Bureau (counterespionage unit) of the Ministry of War, had ordered his agents to shadow her as she made her way between restaurants, parks, tea shops, boutiques, and nightclubs. They opened her mail, eavesdropped on her phone conversations, and kept a log of who she met, yet they found no evidence of her gathering or passing important information to German agents.

In 1916 the war was going badly for the French. Two of the longest and bloodiest battles of the war—Verdun and the Somme—pitted the French against the Germans for months at a time. The mud, bad sanitation, disease, and the newly introduced horror of phosgene gas led to the death or maiming of hundreds of thousands of soldiers. Eventually, French troops became so demoralized that some refused to fight. Ladoux felt the arrest of a prominent spy could raise French spirits and recharge the war effort.

Oblivious to the role being prepared for her, Mata Hari was preoccupied with other matters: She had met and fallen deeply in love with a much decorated, young, Russian captain, Vladimir de Massloff, who was fighting for the French. Before long, Massloff had been exposed to phosgene gas, losing sight in one eye and in danger of going completely blind. Still, when he proposed marriage, Mata Hari accepted happily. She hoped to obtain a safe-conduct pass to take the waters at Vittel for her health, which would place her near where her beloved Massloff was stationed. Mata Hari sought advice from a lover, Jean Hallaure, who worked for the War Department and, unbeknownst to her, the spy chief Ladoux’s Deuxième Bureau.

Hallaure sent her to 282 Boulevard Saint-Germain, which housed both the Military Bureau for Foreigners and the Deuxième Bureau. There, agents told her she could visit her lover if she agreed to spy for France. Mata Hari agreed, and her reward would be a million francs, enough to support Massloff after they married, in case his family disowned him. She did not want to have to deceive him with other men, she wrote.

Ladoux instructed Mata Hari to go back to The Hague via Spain and wait there for instructions. Tellingly, despite several meetings, Ladoux never asked Mata Hari for specific information, never targeted a specific man to seduce, and never provided a reliable means of communicating any secrets she learned to him, or funds. She finally wrote him a letter, sent by regular post, saying she must have an advance to refurbish her wardrobe if she was going to seduce important men.

Betrayed by France

Mata Hari went to Spain, where she boarded the S.S. Hollandia bound for the Netherlands, as instructed by Ladoux. The passengers were stopped en route and Mata Hari found herself once again questioned at a British port. Her encounter in Folkestone the year before made officials even more suspicious of her. She was taken to London by agents for further interrogation, which was carried out in several languages.

As had happened on the previous occasion, nothing incriminating was found on her. But Mata Hari became terrified when they decided to hold her, as they tried to establish whether she was indeed Margaretha Zelle MacLeod or Clara Benedix, a German agent whom she vaguely resembled.

Desperate for release, Mata Hari confessed on November 16 to being an agent for France employed by Ladoux, whom the British authorities then contacted. Ladoux later reported that he answered: “Understand nothing. Send Mata Hari back to Spain.” This was a flat-out betrayal of his own agent. The British files summarize his reply in the following words: “[That Ladoux had] suspected her for some time and pretended to employ her, in order if possible, to obtain definitive proof that she is working for the Germans. He would be happy to hear that her guilt has been clearly established.”

In Madrid Mata Hari decided to find out what secrets of military importance she could learn there. A German diplomat posted to the Spanish capital, Maj. Arnold von Kalle, became enchanted by her beauty and grace. He soon let slip that there were plans for a landing of German officers, Turks, and munitions from a submarine on the coast of Morocco. Anxious to relay this information to Ladoux and claim her reward, she wrote Ladoux asking for further instructions. No reply ever came.

She also established relationships with Col. Joseph Denvignes from the French legation, who fell passionately in love with her. He grew enraged when she dined or danced with other men. To calm his jealousy, she naively explained that she worked for Ladoux and recounted all the secrets she had learned. Denvignes asked her to obtain more information about the Moroccan plan from Kalle, but when she did, her questions made the German suspicious. Since Denvignes was shortly traveling to Paris, Mata Hari wrote a lengthy letter full of information and asked Denvignes to deliver it to Ladoux.

While Mata Hari was conquering the German diplomats in Madrid in December 1916, Ladoux ordered all radio messages between Madrid and Berlin to be intercepted and monitored, using a listening post located on the Eiffel Tower. He later claimed the messages clearly identified Mata Hari as a German spy.

When the exotic dancer returned to Paris, expecting a reward for the intelligence she had passed on, Ladoux refused to see her. She finally made contact, but he denied receiving any communication through Denvignes. When she went the Deuxième Bureau, she was told Denvignes was “unknown.” Only later did it become apparent that there was something odd about the intercepted radio messages from the Eiffel Tower. The French file numbers indicate that the messages naming Mata Hari as a spy were brought to the prosecutor’s attention by Ladoux in April that year, not December and January, when Ladoux claimed they were sent. Seemingly, Ladoux was the only person to have seen the original messages prior to their decoding and translation. It also transpired that the original messages had disappeared from the files.

Even so, the content of these messages were about to be used with devastating effect against the dancer. Later, Ladoux would himself be arrested on espionage charges—but his detention came several days too late to save Mata Hari.

View Images Police mugshot taken soon after Mata Hari’s arrest on February 13, 1917 DEA/GETTY IMAGES

The Trap Closes

By late January 1917 Mata Hari was becoming frantic. Not only had Ladoux shunned her, he also had not paid her. She had not heard from Massloff in some time and was worried that he had again been wounded. She was running out of money and moved to increasingly cheaper hotels in the French capital.

On February 12, 1917, a warrant for Mata Hari’s arrest was issued on the grounds that she was a German spy. The next morning, she was arrested, her room searched, and her possessions seized. Her interrogator was Pierre Bouchardon, the investigative magistrate of the Third Council of War—a hard man, not known to show mercy to suspected criminals, and who was especially disapproving of “immoral” women. His diary reveals his immense hatred for “man-eaters” like Mata Hari.

He placed her in isolation in the most horrific prison in Paris, Saint-Lazare. She slept in flea- and rat-infested cells and had no soap for washing. She was denied access to her possessions, medical treatment, clean clothing, lingerie, and money for food and stamps for letters. She had infrequent contact with her lawyer, a former lover named Edouard Clunet, who was pitifully naive about military trials.

As the days lengthened into months, Mata Hari began to realize that she was in real danger of prosecution. After three months, she fell into a state of extreme anxiety and begged by letter for mercy. She pleaded hysterically to see her solicitor Clunet and especially to see Massloff. Even Massloff’s letters asking her to come visit him in hospital were withheld from her.

View Images At the end of her trial in July 1917, Mata Hari would have to wait nearly three months to be put to death. Her order of execution is pictured here. PAUL FEARN/ALAMY/ACI

Remanded for trial on eight charges, the next phase of Mata Hari’s ordeal began on July 24, 1917. Ladoux’s telegrams and radio messages—now considered to have been doctored—were the only real evidence against her. The seven men who served as jurors were all military men; one, in a memoir, repeated a rumor that Mata Hari had “caused to be killed about 50,000 of our children, not counting those who found themselves on board vessels torpedoed in the Mediterranean upon the information given by [Mata Hari] no doubt.” No evidence brought up at the trial supported these slanders.

Each of the charges against her was vague, mentioning no specific secrets passed to the enemy. Of Mata Hari’s “immoral” lifestyle, however, abundant evidence was presented: One of the policemen who had tailed her through Paris revealed her extravagant spending, as well as her lovers of considerable influence and of diverse nationalities. Even though none of the items in her room indicated espionage, testimony about her personal effects was given at trial. Ladoux testified about the (false) intercepted messages, which showed she was a German agent but not that she had passed any information.

Clunet’s defense was completely ineffectual. He produced some eminent men who testified that Mata Hari was a charming lady who never asked about military matters. Henri de Marguerie, secretary to the French foreign affairs minister and a lover of Mata Hari’s since 1905, defended her fiercely. “Nothing had ever spoiled my good opinion of this lady,” he said. He even accused the prosecutor of accepting a case he knew was false. Indeed, the prosecutor later confessed there was not enough evidence “to flog a cat in the case.”

View Images The women’s prison of Saint-Lazare, Paris, where Mata Hari was held before and after her trial. She spent her last months—and her 41st birthday—in cell 12 here, waiting for her sentence to be carried out. ADOC-PHOTOS/ALBUM

Death Becomes Her

Convicted on all eight counts against her, Mata Hari was sentenced to be executed by a firing squad. Attempts to commute the sentence to a prison term were denied, as were appeals for a presidential pardon. Her execution was carried out in great secrecy early on the morning of October 15, 1917.

Those present at her death included her lawyer, Clunet, the nuns who had looked after her, the prison doctor, and a ridiculously young squad of the Fourth Regiment of Zouaves in khaki uniforms with red fezzes, supervised by the sergeant major of the 23rd Dragoons. She gave a brilliant performance, perhaps her greatest, moving with grace and dignity and refusing to be tied to the stake but standing proud and tall. The sergeant major supervising the squad remarked at the time, “By God! This lady knows how to die.”

Pat Shipman is a writer and adjunct professor of anthropology at Pennsylvania State University who has written widely on both science and history. Shipman’s books on science include The Man Who Found the Missing Link. Her 2007 book, Femme Fatale: Love, Lies, and the Unknown Life of Mata Hari, is published by William Morrow.