Madeleine Maxence Le Veller was born on April 15, 1910, in Évreux, Normandy, France. She was the second of two daughters born to Jean Le Veller, a day laborer, and Louise Gabrielle Latouche, who worked in a factory. When Madeleine was ten years old, her parents separated because of Jean's alcoholism. After the separation, her mother moved the family to Charleville-Mézières.

Madeleine attended school until she was 14 and received her primary education certificate. As a child, she was often described as moody and vain. She had a tendency to lie and sometimes claimed to be of noble ancestry. Her sister Solange remembered that Madeleine would carry around an empty violin case to convince people she was a musician. At the age of 17, she attempted to take her own life by swallowing petrol.

After school, she worked at a buffet in the local train station. There, she met a man named Clément Mouton. They married in 1929 when Madeleine was just 18 years old. The couple welcomed their first child in 1933. During her pregnancy, Madeleine was described as nervous. After some time, Clément joined the Mobile Gendarmerie, which led to rumors that Madeleine had an affair with a garrison officer. When this affair ended, it reportedly caused her distress.

In 1940, Clément was transferred to Constantine, Algeria, and he moved there with Madeleine. During this time, she claimed that the climate affected her life negatively. She began to have many affairs and drinking binges, putting her personal life ahead of everything else. She experienced a difficult pregnancy but tragically lost her child shortly after birth.

Due to her behavior, Clément was transferred to various locations. They moved first to Molière in 1941, and then to Ksar Boukhari, where they had another child. Clément was later transferred to Berthelot, where Madeleine was not allowed to live in the barracks. Because of this, she moved in with a woman named Madame Dez and had her third child a few months later. Eventually, she was allowed to live in the barracks and resumed her social life, reconnecting with old friends from France.

During her time in Berthelot, several suspicious deaths occurred, leading to concerns about Madeleine's behavior. She was known to care for several of the victims. It was around this time that her third child passed away at ten months old. As rumors began to spread, the investigation into her actions would follow.

Madeleine Mouton was arrested in April 1944. Investigators discovered that she had bought 200 grams of sodium arsenite, claiming it was to kill ants. Despite confessing to poisoning four people, she denied the responsibility for others. The first known poisonings occurred in January 1943, starting with Madame Leroux, who fell ill and later died. Her husband, however, survived. During this time, Mouton was not viewed as a suspect and even hosted the Leroux family at her home.

She organized a fundraiser for the Leroux family but allegedly took the money. Mouton's debts increased as she borrowed money from others, claiming it was for education expenses. In April 1943, another poisoning death occurred when Madame Lamasse's mother-in-law died under similar circumstances. Later, in December, an elderly man named Bene also succumbed to poisoning while being cared for by Mouton.

After her arrest, Mouton was taken to a prison in Algiers for psychiatric evaluation. While there, she claimed to have formed a romantic connection with a jailer and pretended to be pregnant. She tried to convince others that she was a political prisoner rather than a violent criminal. A psychiatrist later determined that she was of sound mind and responsible for her actions, noting a lack of remorse.

Her trial began in November 1947, where she faced charges for eleven poisonings, including seven murders. While her lawyer tried to plead insanity, many charges were dropped due to insufficient evidence. Ultimately, she was found guilty on all counts and sentenced to death.

Madeleine Mouton was executed by guillotine on April 10, 1948. On the day before her execution, the executioners pretended to be there for routine tasks and led her to believe her life sentence would be changed. However, when they arrived early the next morning, she was shocked to learn of her execution and fainted. After seeking last-minute spiritual guidance, she was led to the scaffold. Shortly afterward, she was executed, and her body was buried in the cemetery of Sidi Bel Abbès.