Sofas falling over, curtains moving by themselves and a family terrified in their own home – author and investigator Guy Lyon Playfair says the spooky tales of the Enfield poltergeist were real – but the upcoming television dramatisation should be viewed with a pinch of salt.

“The whole family was scared stiff. Terrified,“ says Guy recalling the first time he stepped inside the Hodgsons’ home in Green Street, Brimsdown.

“They were all sleeping in one room with the light on and wouldn’t go into a room on their own, even the bathroom. They were scared out of their wits.“

It was autumn 1977 when he teamed up with Maurice Grosse, a fellow member of the Society of Psychical Research (SPR), to look into claims a poltergeist was terrorising Peggy Hodgson and her four children.

Police and reporters had been left running scared after they saw objects flying about and 11-year-old Janet Hodgson apparently being flung from her bed by some unseen force.

“The first day I was there a marble fell by itself on the floor in front of me,“ recalls Guy, who chronicled the case, which became the most documented paranormal event in the UK, in his 1980 book This House is Haunted.

Now after 35 years it is being brought to the screen in a three-part drama, The Enfield Haunting starring Timothy Spall, Matthew Macfadyen and budding actress Eleanor Worthington-Cox as Janet, who was said to be possessed by the poltergeist.

“The first part is pretty much true, until I get levitated up to the ceiling, which never happened,“ say Guy, now 80.

“Mostly they don’t show the things that did happen. But the thing they did get right was the relationship between Janet and Maurice.“ Maurice had heard about the case from a Daily Mirror article and inspired by his enthusiasm, Guy signed up to help him and spent 14 months investigating, sleeping at Green Street for about 20 nights in total and witnessing numerous unexplained phenomena.

“The weirdest one was seeing this very large armchair flying along the floor backwards just after Janet had gotten out of it. It shot back a couple of feet. Another time the sofa was turned over in a room full of people.

“Then we had all sorts of small things that started moving on their own and flying around the room and disappearing. I remember putting my notebook down on the bed and it shot onto the floor.”

Earls Court resident Guy says he was never scared but became extremely concerned when Janet began to have violent trances which looked like epileptic fits.

“The case wasn’t frightening just frustrating because it wouldn’t stop. We even tried going away but we had a frantic call from the family asking us to come back. That’s what people forget – these things cause families real distress and then some nitwit turns up on TV saying it’s all acting – well by hell is it.

“Yes they did play some tricks on us, but they were awful at it and we knew straight away.“ As members of SPR, a registered charity, their goal was to make the unsettling activity stop – which it did in October 1978 after Guy invited a Dutch medium to visit the house.

“He didn’t speak English very well but he went up to the bedroom on his own and stayed there about half an hour and then came down and simply said ’it’s gone’.

“I was extremely dubious, but it had. It didn’t come back and that was really quite extraordinary.“ Peggy Hodgson and her son have both since passed away, the house has new owners and Guy says the Hodgson family is keen to put the incident behind them.

“I’m still in touch with Janet and she very much wants to be left alone. She’s a long way from Enfield now and is happily married with two boys and has turned down interviews. She just wants to get on with a normal life.“ He also no longer investigates paranormal activity, but is pleased the case is still attracting interest and believes we still have a lot to learn from it.

“Paranormal is simply a word we use to describe something we don’t understand. There’s no indication it’s anything to do with a demonic manifestation.

“There’s a new attitude to reality and how we can change it from people in the scientific world and it’s become quite a respectable area.

“I think it’s a great mistake for anyone to treat it as a joke or simply a creepy story.

“It’s offensive to the victims because when it’s happening to you it’s not funny at all.“

The Enfield Haunting is on Sky from May 3