The True Story: The Exorcist, 5

The recent low-budget hit Paranormal Activity has been laughably hailed by delusional critics as “the most frightening movie ever made”, but it barely scrapes the foothills of the hair-raising ghastliness depicted in The Exorcist. William Friedkin’s demonic-possession shocker was released in 1973, but even today you wouldn’t want to watch it without keeping a large brandy and the off switch within easy reach. This documentary in 5's series The True Story, which tries to find rational explanations for movies, sought to explore the real-life story that the movie, and prior to that William Peter Blatty's novel, was based on.

This wasn’t easy. Leaving aside the fact that there will always be a large body of sceptics who won’t accept a paranormal explanation of anything under any circumstances, the events took place in the late 1940s, so surviving eyewitnesses were thin on the ground. The ones that director Virginia Quinn had been able to track down, such as a certain Dr Alvin Cagey, were dull and unenlightening. The fact that the boy (changed to a girl in the film) at the centre of the events has never spoken publicy about his experiences and still continues to maintain his anonymity cut off the most obvious angle of attack.

Despite all that, the bare bones of the story remain, at the very least, intriguing. How could a 13-year-old boy have the power to move furniture across the floor by staring at it? Where did he find the strength to hurl a fully-grown priest across the room? When questioned in latin about his identity, how on earth did he come up with the reply “I am legions”, indicating that he was possessed by a whole football crowd of demons? And what could explain the way words appeared on his body as though burned there by a  branding iron? Two of these words were "St Louis", which the boy’s family believed was a sign telling them to take him to stay with relatives in that same city. It was in a St Louis hospital run by Catholic monks that the major attempt to exorcise the stricken youth took place.

The main weapon in Quinn’s armoury was the detailed record of the exorcism kept by the priests involved. This described how they spent a month relentlessly reciting the exorcism prayers (in latin and dating back to the 16th century), while the boy writhed, foamed, and screamed obscenities at them. Their attempt to baptise him as a Catholic eventually succeeded, but only after provoking their subject to new heights of frenzy. Then, a week later, the boy supposedly spoke in the persona of St Michael, commanding the Evil One to leave immediately. The symptoms promptly vanished, the boy was able to resume a normal life, and he later went to work for the NASA space agency. Hey, maybe he’d been body-snatched by aliens! No, better not go there.

Could there possibly be a scientific explanation to all this? Of course there could, and the man to deliver it was Dr Michael Persinger, a professor of Behavioural Neuroscience who argued that it was all in the brain. Surrounded by the comforting accoutrements of academe, the Doc calmly laid out the evidence for the way cases of so-called “possession” frequently prove to be a manifestation of “dissociative states” caused by disturbances in the brain’s right temporal lobe. He has even built a device nicknamed “the God helmet” to prove it. Patients put it on, it stimulates the relevant part of the brain, and causes them to experience various kinds of religious or Satanically-possessed sensations. I reckon Tony Blair’s got one of those, not least because Dr Persinger pointed out that most of his “dissociative states” patients are Catholics.

The Vatican doesn’t buy the rationalist argument, oddly enough. The Exorcist movie triggered a revival of the then-unfashionable techniques of exorcism, which have now made such a resounding comeback that the Vatican runs full-time exorcism training courses. As the philosopher Dylan tells us, “you either got faith or you got unbelief, and there ain’t no neutral ground.”

five.tv's The True Story series continues on 5 on Sunday 27 December with the real-life incidents behind The Bourne Identity.

Buy The Exorcist on DVD. Find The Exorcist original book and related books