In 1981, the clean-cut town of Brookfield, Connecticut was celebrating its 193rd year without a homicide when their streak came to an abrupt end.

It was a quiet evening in February when Arne Cheyenne Johnson plunged a five-inch pocket knife Alan Bono’s chest, repeatedly. He died an hour later. Johnson was picked up two miles from the scene by police.

Months later he stood in the dock and pled not guilty saying the devil made him do it.

His trial earned notoriety as The Devil Made Me Do It case, the first known court case in the USA in which the defense sought to prove innocence based on the claim the defendant was possessed.

Attorney Martin Minella claimed Johnson was possessed and he had the evidence to prove it.

“The courts have dealt with the existence of God. Now they're going to have to deal with the existence of the Devil,” he told the New York Times in 1981 a month after the stabbing.

If that wasn’t strange enough the defence team argued it all started with Johnson’s fiance’s brother 11-year-old David Glatzel.

They claimed he had been ‘cured’ of demonic possession only for the demon to jump into Johnson.

Now the case is back in the spotlight after James Wan hinted what the next Ed and Lorraine Warren case to make it to the big screen could be.

Speaking about the plot of The Conjuring 3, Wan, who was at the helm for the first two movies, teased the film will be based off another real-life case of the Warren's - the paranormal investigators at the heart of the franchise.

“It’s not necessarily based on the artifact,” he said. “But it’s based on one of the Warren’s case files...It’s this guy who was on trial for committing a murder. I think it’s the first time in America’s history where the defendant used possession as a reason, as an excuse.”

The Devil Made Me Do It case seems the most likely suspect.

On November 24, 1981, Johnson was convicted of first-degree manslaughter for killing his landlord Alan Bono in Connecticut.  He served five years of his 10-20 year sentence.

The murder and trial made headlines around the world, with the Warrens at the heart of the media storm.

While the judge ruled that his defence could never be proven and was therefore infeasible in a court of law, the story behind it fascinated the world.

David Glatzel and demonic possession

The case really began when David’s sister Debbie Glatzel called in Roman Catholic priests and the Warrens to help.

“He would kick, bite, spit, swear -terrible words,” she told them at the time. “He experienced strangling attempts by invisible hands which he tried to pull from his neck, and powerful forces would flop him rapidly head-to-toe like a ragdoll.”

David’s mother Judy said he would wake up screaming about a “man with big black eyes, a thin face with animal features and jagged teeth, pointed ears, horns and hoofs” who told him to “beware”.

The boy didn’t watch horror movies and wasn’t known to lie.

Debbie asked her fiance to stay with the family to help out and see if it would break David out of his ‘phase’ - that fiance was Johnson.

The nightmares didn’t go away, instead, they got worse.

Bruises and scratches appeared on David while he slept and strange noises were heard in the attic, but the family couldn’t find a reason for them.

Then David began to see the Beast Man while he was awake. He claimed to see “an old man with a white beard, dressed in a flannel shirt and jeans.”

Desperate the family turned to the Catholic Church for help and a priest blessed their home - apparently, all it did was annoy the Beast Man.

The noises grew louder, the visions became stronger, and David started to act strangely; hissing, speaking in different voices and quoting from the Bible and Milton’s Paradise Lost.

The family began to take turns watching David overnight in shifts as he often woke up and experienced seizures.

It was time for the Warrens the self-professed “demonologists”.

Speaking to People magazine Lorraine said: “While Ed interviewed the boy, I saw a black, misty form next to him, which told me we were dealing with something of a negative nature. Soon the child was complaining that invisible hands were choking him—and there were red marks on him. He said that he had the feeling of being hit.”

While this was happening, David’s parents sought psychiatric help and were told he was “normal” but had a “minimal learning disability”.

The Warrens were convinced he was possessed.

“David would be doodling and he’d be concentrating, then he’d look up and it was no longer a little 11-year-old boy,” Lorraine said .

The local diocese admitted to investigating the case but never released any details.

Lorraine and Ed, along with a group of priests, held three “lesser exorcisms” where they claimed David levitated, swore, stopped breathing and even demonstrated precognition, predicting the murder Johnson would go on to commit.

“We know there were 43 demons in the boy,” Ed said. “We demanded names, and David gave us 43.”

Johnson taunts the demons

Then in October 1980, the Warrens warned the police the situation was about to get even more dangerous.

According to Ed, it was during one of the exorcisms that Johnson made his “fatal mistake”, and taunted the demons that David was reportedly possessed by.

“Take me on, leave my little buddy alone,” he cried.

TV series The Haunting states a few days after the incident Johnson was attacked by the demon that “took possession of his car and forced it into a tree”. Johnson was unharmed.

David’s condition worsened and Debbie, along with Johnson, felt it was time to move out. Debbie was hired by Alan Bono as a dog groomer, and she rented a place near her work.

Soon Johnson started to behave strangely.

Debbie said he would fall into trances, he’d growl and hallucinate. “Later he would have no memory of it. It was just like David,” she said.

The day of the murder

Then on February 16, 1981, Johnson called in sick to work. He joined Debbie at the kennel along with his sister Wanda and Debbie’s nine-year-old cousin Mary.

The group had lunch with Bono, drinking heavily, then Debbie took the girls for pizza while Johnson remained behind.

They returned to find Bono agitated and drunk. He grabbed Mary refusing to let go.

According to Wanda her brother challenged Bono and ordered him to release Mary and, as the little girl ran for the car, Debbie stepped in to calm things down.

Johnson growled “like an animal”, drew the five-inch knife, and stabbed Bono again and again.

According to Johnson's lawyer, Bono suffered "four or five tremendous wounds", most of which were to his chest, and one that stretched from his stomach to the bottom of his heart.

The aftermath and trial

The next day Lorraine told the police she felt Johnson was possessed at the time of the murder. The Demon Murder trial made headlines around the world, the Warrens were everywhere.

Johnson’s lawyer Minnella flew to London to investigate similar cases, though they’d never gone to trial, and he planned to fly in specialists as well as subpoena the priests who carried out the exorcisms.

The trial began, but the judge rejected the unusual defense saying it would be "irrelative and unscientific" to allow related testimony.

The jury convicted Johnson of first-degree manslaughter and he was sentenced to 10 to 20 years in prison - he served five.

Where are the Glatzels now?

While Johnson was convicted the drama was far from over. David had gone from a smiling little boy to a disturbed overweight child, and while the attacks had lessened they hadn’t gone completely. His mother still clung to hope as the trial rumbled on.

“There is a God, and He will answer our prayers,” she said.

Their experience was made into a book by Gerald Brittle who wrote The Devil in Connecticut with Lorraine Warren’s help.

The family argued they’d been taken advantage of.

Lorraine said the profits were shared with the Glatzels - it was confirmed $2000 was paid to them.

However, when the book was re-published in 2006, David and his brother Carl sued the authors and publishers for violating their privacy, libel and "intentional infliction of emotional distress."

Carl argued the book and story was a hoax conjured up by the Warrens for monetary gain. Carl is writing his own book, Alone Through The Valley about his version of events.

Lorraine has defended the Warrens involvement and denied Carl’s claims.

Brittle has said the “family wanted the story told” and he has in his possession video of more than 100 hours of interviews with them.

David’s father denies his son was possessed, but Johnson and Debbie - who got married - support the Warrens’ account.

How closely The Conjuring 3 will follow the case file is to be seen, but whatever they decide there’s no denying The Devil Made Me Do It case is fascinating whether you believe in possession or not.