A Disturbing Journey into the Depths of Shared Psychosis:

"Folie à deux," or "shared psychosis," is a rare shared psychotic disorder in which a dominant individual typically convinces another person of their delusions. One of the most shocking recent examples in history is the case of the French au pair girl Sophie Lionnet, who was killed by Sabrina Kouider, the driving force in this case, and Ouissem Medouni.

Lionnet was starved and tortured by the couple, and her body was eventually burned in the garden of their London home.

By committing this murder, Kouider and Medouni joined the ranks of killer couples, which include some of the most infamous killers we know.

ROSEMARY AND FRED WEST

Rosemary and Fred West are one of the most famous examples and two of Britain's most notorious murderers. They were active between 1967 and 1987. Fred had already raped and killed before he met Rosemary.

Rosemary was the perfect match for him: she was a woman who not only tolerated his crimes but also convinced young women to follow her into the couple's house in Gloucester. The girls were then held captive in the basement, where the couple would rape and torture them. When they grew tired of their victims, they would kill and dismember them, burying their remains near their house. By the time the police obtained a search warrant for the property, the couple had killed at least 12 victims, including two of their own daughters and allegedly Fred's first wife.

Fred was charged with 12 murders, while Rose was charged with 10. Fred committed suicide before his trial, and Rose was sentenced to life imprisonment.

IAN BRADY AND MYRA HINDLEY

Equally infamous are the Moors murderers Ian Brady and Myra Hindley. The couple was active between 1963 and 1965, killing five children between the ages of 10 and 17.

Brady and Hindley met at work when Myra was only 18 years old. In 1963, Brady wanted to commit the perfect murder, and so the two killed their first victim: Pauline Read. Similar to the Wests, Myra was responsible for luring the victims after Ian selected them. Over the next two years, the couple killed four more children, sexually assaulted them, tortured them, and murdered them. Their bodies were buried in the Saddleworth Moors. The two were convicted of their crimes. Myra died in 2002, and Ian died in 2017.

KARLA HOMOLKA AND PAUL BERNARDO

Similar crimes were committed in Canada by Karla Homolka and Paul Bernardo, known as the "Barbie and Ken Killers." The couple met in the 1980s when Karla was 17 and Paul was 23. At that time, Paul was already regularly raping women and was known as the "Scarborough Rapist."

Karla supported him, and together they killed at least three young women. The first was Karla's sister, Tammy. Karla had promised Paul Tammy's virginity as a "gift." The two drugged Tammy, and then Paul raped her while Karla filmed the act. Tammy began choking on her own vomit. Although the couple called emergency services, the paramedics were unable to revive her. After Tammy, the couple raped and murdered 14-year-old Leslie.

ELIZABETH HAYSOM AND JENS SÖRING

It is not always the man who dominates a relationship. Elizabeth Haysom was 22 when she met Jens Söring in the 1980s at the University of Virginia.

Together, the two murdered Haysom's parents. Their actions were so brutal that they nearly decapitated their victims unintentionally. They then fled to England, where they were arrested for fraud. Haysom was diagnosed with borderline personality disorder, and Söring with "folie à deux."

Elizabeth pleaded guilty to two counts of murder before the act and was sentenced to 90 years in prison. Although Jens initially confessed, he later recanted and claimed that Haysom had committed the crimes. It was solely Söring's confession that allowed the prosecution to charge him. None of the DNA found at the crime scene could be attributed to him. However, he was still found guilty of first-degree murder in two cases and sentenced to life imprisonment.

JASMINE RICHARDSON AND JEREMY STEINKE

In a similar case, 12-year-old Jasmine Richardson persuaded her 23-year-old boyfriend, Jeremy Steinke, to kill her parents and younger brother. The two fled the crime scene but were quickly apprehended. Steinke was sentenced to three life terms in prison, while Richardson was released in 2016 after serving a 10-year sentence. Considering that Steinke claimed to be a 300-year-old werewolf, three life sentences are nothing...

HENRY LEE LUCAS AND OTTIS TOOLE

One particularly violent pairing was that of Henry Lee Lucas and Ottis Toole. After meeting in 1976, the couple allegedly committed 108 murders together, although Lucas confessed to over 3,000. Both were convicted and died in prison.

ERIKSSON TWINS

The shared madness is not limited to couples, as demonstrated by the identical Eriksson twins. Swedish sisters Ursula and Sabina traveled to London by bus in 2008. However, during a stopover, their behavior became so strange that the driver refused to let them back on the bus. They were then caught on video surveillance running along the busy M6 motorway, attempting to cross it. This led to chaos and Sabina being struck by a car.

The police came to their aid, but while in custody, Ursula managed to escape and ran into oncoming traffic again. Sabina followed her and was struck head-on by another car. Both survived the incident but refused any medical assistance. Sabina then attacked an officer and once again ran into traffic.

After Sabina was released from police custody shortly thereafter, a man offered her a place to stay. The next day, she stabbed him to death. She fled the scene and jumped off a bridge onto a road. She was arrested in a hospital after the incident.

The cause of the sisters' behavior remains uncertain. There were no indications of drug or alcohol use.

Note: Some details and specific cases mentioned in the original article may have been condensed or omitted for brevity and clarity in the rewritten version.