Folie a deux (“madness of two”) is also known as shared psychosis. Without getting too much into the medical terminology or in any way implying that this is anything other than a layman’s list, folie a deux is when two or more people share the same delusions.
Usually, folie a deux occurs when people are very close. Sufferers are often related by ancestry or marriage. Sometimes, they are just living together. The disorder has a high correlation with people who are isolated outsiders, but this is not always the case.
Sometimes, participants in folie a deux are harmless people whose delusions only affect themselves. Other times, they are criminals who hurt or even murder people.
Whatever they do, it’s an interesting psychological phenomenon that seems outlandish and impossible to the average person, even though it has happened repeatedly.
10 ‘Margaret And Michael’
In the 19th century, the first reported case of folie a deux involved “Margaret and Michael,” a married couple. Both were 34 years old. They shared delusions that certain people they knew were persecuting them.
Together, they agreed that these unnamed persecutors were entering their house, spreading around dust and fluff, and wearing down the couple’s shoes.
Although the real identities of Margaret and Michael will most likely never be discovered, they are notable less for their issues with fluff and shoe use and more as the first couple diagnosed with folie a deux.
9 Folie A Trois
Three Sisters From South Carolina
Sometimes, folie a deux, trois, or famille is used as a legal defense to help diminish the capacity of the defendant(s) in the eyes of the court. In the case of three biological sisters from South Carolina, the diagnosis of folie a trois led to successful insanity defenses in their respective trials for various criminal wrongdoings.
The lives of the three sisters became increasingly enmeshed as adults, even though they had led ordinary, respectable lives before spending all their time with only each other. They became increasingly concerned that their mother, who also suffered from mental illness, was going to hurt the three children of one of the sisters.
They also became preoccupied with religion. The sisters stopped sleeping and became convinced that God was communicating with them. When the husband of one put a stop to them living in the same house, the women felt compelled to put on pajamas, take the three children, and drive to a house that they believed God had given them so that they could live together.
They forced their way in, attacking the residents of the house and the attending police officers.
The sisters were charged with multiple offenses and put in a cell together. There, they took off all their clothes, refused to clean themselves, and performed religious rituals. They attacked anyone who came through the door of the cell. It took two hours for 15 officers to quiet the three sisters and cuff them.
None of the sisters had a previous criminal record. They are no longer allowed to live near each other or visit without supervision.
8 Folie A Deux With A Pet
Volume 149 of the American Journal of Psychiatry recounts a case of folie a deux shared between an 83-year-old widow and her pet dog.
The woman had come to the conclusion that her upstairs neighbor was moving furniture around to deliberately annoy her. This progressed to believing that he was trying to force her to flee her home.
She believed that he was attacking her and her pet with “violet rays,” so she made the dog an “air raid shelter” under the kitchen table. Whenever there was a noise coming from above, the dog would run and hide in its spot.
Now whether this was actual folie a deux or whether the dog was just doing what its owner wanted it to do is questionable. But whatever the dog’s real motivation was, it was participating in the delusion.
7 Folie A Deux, Religion, Demons, And Murder
Mr. and Mrs. A were both lonely young adults who met each other, fell in love, and married. It seemed like a match made in heaven for the girl who spoke to the sea and night sky and the boy who had been diagnosed with paranoid schizophrenia at age eight. But it led only to murder and eventual separation.
Having met through a personal ad, Mr. and Mrs. A were married after knowing each other for only a week. They both came to believe that one of the “demons” who spoke through Mr. A was the childhood “god of the sea” who conversed with Mrs. A. Sounds perfect, doesn’t it?
For several years, the couple traveled around, trying to find work and following the directions of Mr. A’s demons. One of the demons told Mr. A that he would be killed imminently and that Mrs. A would be raped. The couple bought a gun.
While eating one night at a restaurant, Mr. and Mrs. A perceived that two male diners were laughing at them. Upset, Mr. and Mrs. A returned to their apartment. But the demons told them to go back to the restaurant and kill the diners. They ran back and shot the two unknown men dead.
Mr. and Mrs. A are now divorced.
6 Nathan Leopold And Richard Loeb
In 1924, America was horrified by the folie a deux of Nathan Leopold and Richard Loeb, two heartless teenage boys.
Leopold and Loeb were lovers, with Loeb being the dominant personality of the pair. In fact, his dominance over Leopold, who came to share Loeb’s delusional way of thinking, led to what is known as folie imposee, in which a dominant person’s delusions are taken on by his submissive partner.
Leopold was a genius with an IQ higher than that of Einstein. As an academic prodigy, an all-around unpleasant person, and an outsider who thought that he was superior to others, Leopold believed that his inherent qualities exempted him from the social rules that governed all other people.
Loeb was also a brilliant scholar and the youngest person of his time to have attained a degree at the University of Michigan. Whatever Leopold lacked in attractiveness, grace, and popularity, he found in his new love, Loeb. They had a secret relationship because homosexuality was frowned upon at the time.
The pair became obsessed with reading detective fiction and true crime, and they embarked on their own crime spree together under Loeb’s instructions. They set fires and broke into buildings, playing a game that committed them to have sex after each crime.
Then they lured 14-year-old Bobby Franks to their rented car and bludgeoned and suffocated the terrified boy to death. Leopold and Loeb staged a fake kidnapping of the child and tried to cover their tracks. But soon their “perfect crime” was solved, and they were in court, smiling and laughing and performing like celebrities at a red carpet event.
Loeb was killed in prison. As he died, he was held in the arms of his lover and soul mate, Leopold.
5 Christine And Lea Papin
Christine and Lea Papin were French sisters who worked as housemaids in the home of Rene Lancelin, his wife, Leonie, and their adult daughter, Genevieve.
The Papin sisters were the product of a dysfunctional and abusive home. Their father had raped their elder sister, and all three girls had been sent away as children to live with other families. Eventually, they went to orphanages and convents.
Sharing a room together and socially isolated, the sisters were quiet and uncomplaining. When Christine was 27 and Lea, the more submissive sister, was 21, the women entered the psychological history books.
During an argument with Leonie Lancelin, Christine suddenly changed from a well-behaved cook to a murderous monster. She gouged out Genevieve Lancelin’s eyes with her bare hands. Joining in, Lea followed suit with Madame Lancelin. The pair savagely murdered the mother and daughter, exposing their bodies in a way that indicated a sexual element to the crime.
When Rene Lancelin returned home with his son-in-law, he called the police because he was locked out of the house. The police found the ladies of the house dismembered all over the floor. Fearing that the same fate had befallen the maids, the officers were shocked to find the sisters locked in their room, by some accounts naked in bed together.
The sisters confessed and were taken into custody.
In the years that followed, the sisters were separated and studied. The separation caused Christine especially intense distress. When the women were allowed to meet, it was indicated that they were in a sexual relationship together. Despite the popular opinion that this was the case, a sexual relationship was never proven and was denied by their own doctors.
Their defense attorney suggested that their personalities had become so enmeshed that the personality of the submissive sister, Lea, had ceased to exist and they both shared the paranoid delusions associated with folie a deux.
4 Pauline Parker And Juliet Hulme
Pauline Parker and Juliet Hulme were 15-year-old schoolgirls from Christchurch, New Zealand.
Passionately close, they were obsessed with each other. They lived out elaborate fantasies, and together, they dreamed of becoming Hollywood actresses and novelists.
Their parents became worried about their codependent relationship and wanted to separate them, especially after Pauline’s psychiatrist told her parents that she was having a sexual relationship with Juliet. However, that claim has been denied by Juliet in more recent years.
When the marriage of Juliet’s parents disintegrated, the girls were set to be separated. Juliet was to leave New Zealand with her father. Both girls wanted Pauline to move with Juliet, but all the parents refused.
In 1954, Pauline’s mother, Honora, took the two girls on an outing and the girls brutally murdered her.
The legal plea of insanity did not hold up. After only a few years in prison, the women assumed different identities and both moved to the UK, although not together. The woman who was Juliet Hulme became the successful crime author Anne Perry, while the former Pauline Parker became equestrian teacher Hilary Nathan.
The 1994 movie Heavenly Creatures is based on the girls’ relationship and the murder of Honora Reiper. Anne Perry has claimed that the movie is nothing more than fiction. She has also suggested that she took part in the murder so that Pauline Parker would not kill herself if they were separated.
3 Morgan Geyser And Anissa Weier
Even younger than Parker and Hulme were Morgan Geyser and Anissa Weier, who were 12 when they decided together to commit a murder.
Weier and Geyser, who has schizophrenia and psychotic spectrum disorder, stabbed their classmate Payton Leutner as a sacrifice to the fictional horror character Slender Man.
Weier was the new best friend of Geyser, who was also best friends with the victim. This trio of misfit girls was playing together at Geyser’s birthday party sleepover just before the plans of killing Leutner came to fruition. Weier and Geyser stabbed Leutner in a nearby park and then walked her into the forest to die.
The two girls were picked up by the police on their way to the Nicolet National Forest where they believed that they were going to be welcomed into the house of Slender Man, having paid his price of sacrifice by killing Leutner.
They did not know that Leutner had survived.
Slender Man is a tall, lanky man in a suit who has blurry facial features and steals children. Geyser and Weier had wanted to prove that Slender Man exists. So they lured their classmate into the woods. Geyser held Leutner down while Weier stabbed her. They thought that this sacrifice would enable them to live in Slender Man’s mansion.
Left for dead, Leutner managed to crawl out of the woods with multiple stab wounds. Still clinging to life, she was found by a passing cyclist, who called for medical help.
Both attackers were found not guilty by reason of mental disease or defect. Geyser and Weier were sentenced to 40 years and 25 years, respectively, in a mental institution.
2 Folie A Famille
The Tromp Family
One of the most perplexing stories of shared delusion is the case of the Tromp family.
In 2016, the Tromps of Silvan in Victoria, Australia, left their berry farm and went on a wild, nonsensical road trip that led to an equally wild manhunt for the missing family. By all accounts, the Tromps were a normal family and respected members of their community. So this behavior was very out of character.
Along with their adult children, Riana, Ella, and Mitchell, Mark and Jacoba Tromp got into a vehicle and left their property abruptly.
Mark Tromp was suffering from a mental breakdown at the time. However, his family believed his delusions that people were out to harm the family and that escape was necessary. They left everything—phones, wallets, passports. Their house was unlocked, and their farm and business vehicles all had keys in the ignitions, ready to go.
The family fled in desperation but soon got separated. On the second day of the trip to New South Wales, the siblings decided to leave the car because they were terrified about what was going to happen. Mitchell left the family in Bathurst. Confused and bewildered, he headed to Sydney and then back to Melbourne by train. Ella and Riana decided to leave and headed to Goulburn, where they got separated.
Riana was found catatonic and hiding in the back of a pickup. She received medical attention. Ella stole a car and headed for home. A few days later, Jacoba was discovered wandering around the small town of Yass and was taken to the hospital. Mark was eventually found near Wangaratta, still trying to evade the people whom he believed were trying to kill him.
The close-knit, loving family is back home now. They have resumed life on their farm and are healing from their traumatic experience. Fortunately, no one was hurt. They have all received medical and mental health care.
1 Ursula And Sabina Eriksson
Swedish twins Ursula and Sabina Eriksson came to international attention with the official “Weirdest Thing The Author Has Ever Seen On The Internet.”
In 2008, Ursula lived in the US, and Sabina resided in Ireland with her husband and two children. In May of that year, Ursula went to visit Sabina. The pair unexpectedly took off for England, leaving Sabina’s children behind. They visited a police station and reported that Sabina was worried about the children.
Then they took a bus to London. They were kicked off the bus for acting strangely and refusing to check their bags. Dumped at a service station, they were reported to the police on suspicion of having bombs. They did not, and they were free to go.
This is where it gets weird.
The twins were walking down the middle of the M6 motorway when a crew for TV show Motorway Cops was filming there. The film crew noticed the women dodging around the traffic.
The police started talking to the women when Ursula suddenly ran into traffic and was run over by a truck. While she was being attended to, Sabina ran onto the motorway and was hit by a small car.
Ursula tried to get up and told the police that they weren’t real police. She attacked them. Sabina got up and ran away, also assaulting a police officer. She screamed something about organ stealing but was recaptured. With the help of passersby, both sisters were put in an ambulance. It took six people to wrestle Sabina into the ambulance.
Ursula’s legs were crushed, so she remained in the hospital. But Sabina was put in police custody. It was discovered that the sisters were carrying multiple cell phones in their bags and that Sabina’s husband had no idea where she was.
After her release from police custody, Sabina was invited to stay in the home of Glenn Hollinshead, a man she met soon afterward. Her behavior remained odd, talking to him and a guest about poisoned cigarettes. She stabbed Hollinshead to death the next morning.
Sabina then left that house and walked along, beating herself in the head with a hammer. When a passing driver tried to stop her, she beat him in the head with a roof tile that she had in her pocket.
Then Sabina ran, jumping from a bridge to land on the A50 highway, 12 meters (40 ft) below. She broke multiple bones, which eventually slowed her down enough to be caught. Although Sabina was sentenced to five years in prison for murder, she was released in 2011 and returned to Ireland. Her sister had already gone back to the US.
Alone, they were normal people. Yet, for some reason, they became self-destructive, violent participants in folie a deux when they were together.