In an ordinary house in a north London suburb in the late 1970s, children levitated, objects flew across rooms, heavy furniture moved on its own and a young girl was flung from her bed.
Twelve-year-old Janet Hodgson even sometimes spoke in the rasping, disembodied voice of a man who had died in the house over a decade earlier.
In recordings, the ghost of Bill Watkins recounted how he died and where he had been buried, in a case that was quickly dubbed the "Enfield poltergeist".
Journalists, photographers and paranormal investigators all descended on the house to try to document the apparent haunting.
Now, 45 years later, a stage play and a new Apple TV documentary exploring the goings-on at 284 Green Street have sparked fresh interest in the mystery.
Writer Paul Unwin's drama "The Enfield Haunting", starring Catherine Tate and David Threlfall, revisits the story and opens at London's Ambassadors Theatre on Thursday.
He said he had no particular interest in the saga until 11 years ago, when his agent's husband suggested it might make a good play.
A few weeks later, Unwin found himself in the basement flat of paranormal investigator Guy Lyon Playfair, hearing at first hand about the events that unfolded over 18 months in 1977-78.
Unwin listened to parts of the many hours of recordings that Lyon Playfair had made at the house with fellow paranormal investigator Maurice Grosse.
- Remote camera -
According to Unwin, as soon as Lyon Playfair pressed "play" on a recording of the deep, gruff voice, he realised it could not be produced by a young girl -- even one with ventriloquy skills, as sceptics suggested.
At the same time, some of the things the voice said came across as the sort of things a child might say if they were pretending to be a ghost.
Leaving the London flat five hours later, Lyon Playfair asked Unwin if he believed what he had heard.
He could only reply that he "didn't know".
"I went in a sceptic and came out full of shivers about some of the things he described and some of the tapes that he played me," Unwin told AFP.
More than four decades on, people remain split between believing there had been real paranormal activity and that it was all the result of pranks by Janet and her older sister.
Although it seems likely that the girls faked some of the events, Lyon Playfair and Grosse remained convinced there had also been significant paranormal events in the house.
Both the sisters took part in the Apple TV documentary, along with press photographer Graham Morris.
The former Daily Mirror photographer eventually came to the conclusion that "a force" was following Janet around.
He used a remote camera to capture the moment she was apparently flung from her bed in the middle of the night.
- 'Extraordinary events' -
One of the resulting photographs showed Janet lying flat in bed followed a split second later by another of her in mid-air.
Morris said the sequence was taken a sixth of a second apart, so if Janet had climbed out of bed and then jumped into the air it would all have been captured on film.
Unwin said he had always been interested in how duress can heighten emotions and "can lead people to believe things that are both crazy, bizarre, some really unreal".
But he stressed that his play was not a documentary.
"It's what I imagine might be going on in a house where there is a working-class single mother in the 1970s who is trying to bring up two wayward girls and two other children... and the pressures that then brew," he said.
One of the things that attracted him to the story was that, unlike most ghost tales, it was not set in a vast, creaking mansion on a desolate moor.
"This is a still-existing 1930s small working-class house in a street in Enfield.
"This family were so ordinary and yet these extraordinary events occurred."
He declined to be drawn on any conclusions he may have drawn, explaining, cryptically, that it can all be "played both ways".
"The play is my response to what I heard and the play does have a ghost in it," he said.
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