The Exorcist true story: Real case behind 1973 William Friedkin film - what is 2023 sequel Believer based on?

The Exorcist, a terrifying film about a possessed child and the priest who tries to save her soul, directed by William Friedkin who died on Monday, landed in cinemas half a century ago.

The film was made on a budget of $12 million and went on to gross more than $420 million, and even today it is still one of the top 10 highest earning horror movies ever, without adjusting for inflation. 

The Exorcist ushered in the blockbuster era, gained 10 Oscar nominations (and two wins), spawned a wave of disappointing sequels, and became an urban legend.

Today the film is iconic, regarded as one of the scariest films of all time, and because of its creepy subject matter, the film has been mythologised; those who saw the film in the cinema half a century ago recall seeing audience members pass out in their seats, or break out in hysterics, from sheer terror.

But what’s even spookier, is that The Exorcist is actually based on a true story, or at least a real account of a story that may have been true, depending on your spiritual outlook.

Was The Exorcist inspired by a true story?

Author William Blatty, who penned The Exorcist in 1971, was said to have been inspired by a story of an exorcism, rumoured to have actually taken place.

Some time during his studies at Georgetown University in Washington DC, where he attended from 1950-54, Blatty learned about the supposed possession and exorcism of a 14 year old boy in 1948.

The boy, Robbie had grown up in a religious household and taken an interest in occult items such as Ouija boards. Following the death of Robbie’s aunt, the family began to suspect a paranormal presence in their home.

They heard strange noises and vibrations as well as flying objects when Robbie was nearby. Robbie’s parents contacted the church and it was reported that Catholic priests performed a series of exorcisms on him. The exorcism has taken on a mythical quality and it was believed Robbie’s bed began to shake during the final stages - he also broke the priest's nose.

By all accounts the exorcism was eventually successful, and Robbie went on to lead a normal life.

After learning of this fascinating case, Blatty used elements of what he had heard and read in his own novel, including the strange phenomena that took place in the early stages of a possession, some of the exorcism rituals, and, of course, the shaking bed.  

Blatty is also believed to have been inspired by a much older possession story - the Loudon possessions of 1634. 

These possessions surrounded a group of nuns who claimed to have been overcome by a demonic spirit when they had taboo dreams about an attractive priest. Supposedly, the nuns would cry out, blaspheme, and make rude gestures when possessed. 

The priest in question, Urbain Grandier, a known historical figure, was blamed for the possessions, accused of witchcraft, and burned at the stake.

In Blatty’s novel Regan, reacts in a similar way as the nuns to possession - she also makes highly lewd remarks, and does something very unfortunate with a crucifix. 

When The Exorcist was picked up by Warner Bros and turned into a movie, Blatty adapted his own novel into a screenplay, and Friedkin came on board as director.

The pair became friends during production but fell out over creative differences, as Friedkin cut several scenes from the film that Blatty felt should have been kept. They later made amends and Friedkin recut the film for a 2000 re-release, with many of the cut scenes re-added. 

Is The Exorcist: Believer based on a true story?

The Exorcist: Believer is a direct sequel to the 1973 film, set in the present day and focused on new victims.

When two young girls go missing, their families are desperate to find them, but when the pair reappear, they begin to act strangely. It becomes apparent that the children have been possessed, and Chris MacNeil, Regan’s mother from the original film, again played by Ellen Burstyn, is called on to help.

The script is based on characters created by Blatty, but is not an adaptation of another of his novels. The screenplay was written by the author of the Halloween reboot trilogy, David Gordon Green, and newcomer Peter Sattler.

The sequel is believed to be an original story and not based on any specific real life or rumoured diabolical events, but still based in the same world as Blatty’s original novel. Believer is slated to be the first of three new sequels, the next instalment will be titled The Exorcist: Deceiver.