The film is being released nationwide in the UK to celebrate the film's 25th anniversay, and here, for one last time, Mark Kermode explains what all the fuss is about.

When The Exorcist opened in America on Boxing Day, 1973, the response was immediate and extraordinary.

A riveting depiction of the demonic possession and subsequent exorcism of a young girl in Washington D.C., the film struck a unique chord with American audiences.

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Following in the wake of William Peter Blatty's best-selling novel, and fuelled by press speculation about a 'curse' on the production, The Exorcist became the Titanic of its day, with audiences going to any lengths to see the movie.

In New York pundits bracing freezing snows and blizzards to queue round the block, while ticket touts commanded outrageous sums for a good place in line for the next performance.

The Exorcist prepares himself

In Los Angeles, additional matinees and late night screenings were added at the Westwood and The Bruin where record breaking crowds turned out for The Exorcist, a phenomenon that was repeated across the country.

Dominating world news

Breaking out of the entertainment pages, The Exorcist became an event picture which dominated the news both in America and around the world.

While local and national news stations ran features on both the novel and film, Walter Cronkite devoted a full ten minutes of his legendary news programme to 'The Exorcist Phenomenon' and the history of demonic possession.

In print, newspapers and magazines were equally enthusiastic, with the respected New York Times devoting an unprecedented six articles in their weekly section to The Exorcist, while Newsweek ran front cover features and in-depth reportage.

Such reactions were later mirrored world-wide -- In Russia, for example, The Exorcist became the only movie ever to be reviewed on the front page of Pravda.

Regan after possession

In Milan, the audience at a packed news conference refused to leave a museum where William Friedkin and technical advisor Father Thomas Bermingham were answering questions about The Exorcist - in the end the museum had to shut off the power to clear the auditorium.

In Rome, The Exorcist made the national news once more when a sixteenth century church across the street from a cinema where the movie opened was struck by lightening, causing an ancient cross to plummet from its roof onto the pavement below.

Overpowering the audience

For some viewers, the experience of watching The Exorcist proved overpowering.

At a preview screening in New York, one audience member had to be helped out after becoming dizzy, provoking a wave of press reports of fainting, vomitings, and other hysterical reactions.

By the time The Exorcist opened in the UK, rumours of its traumatising power had grown to such proportions that the St. John's Ambulance Brigade were regularly called to attend screenings armed with stretchers and to minister to the faint-hearted.

'A deeply spiritual film'

Nevertheless, praise for The Exorcist was widespread, from broadsheets to religious publications, with the arch-conservative conservative Triumph magazine publishing a rave review in 1973, echoing Father Kenneth Jadoff's claim in The Catholic News that 'The Exorcist is a deeply spiritual film.'

According to director William Friedkin, a copy of the film was supplied to high ranking Catholic Father Pedro Arrupe in 1974 following a favourable viewing and subsequently remained with his offices.

Mother and disturbed daughter struggle

Support from such circles continues to this day.

Earlier this year, Catherine Von Rhuland of the New Christian Herald declared: "'The Exorcist is surely an explicitly Christian film [in which] the ministry is presented with dignity as an honourable vocation [who] go the full distance with Utter Darkness -- a sleeves rolled up, no-holds-barred fight to the finish between God's earthly representatives and Satan."

Such reactions are unsurprising, since Friedkin's movie was written and produced by the Catholic writer William Peter Blatty whose multi-million selling novel was praised by the Vatican literary journal Civilta Cattolica having been described by the author as "a 350 page thankyou note to the Jesuits."

Quotes used in mass

Indeed, such is the standing of Blatty's novel within the Catholic establishment that last year Cardinal O'Connor read sections from it as part of his Sunday mass in St. Patrick's Cathedral in New York.

Blatty himself remembers being told by Father Bud Markey that in the wake of the opening of the film he "had a run on the confessional box" from people who hadn't been to church in years, an assertion widely echoed by others in the priesthood.

According to Father Thomas Bermingham and Father William O'Malley of Fordham University in the Bronx, The Exorcist is still shown to students every year, and still continues to provoke lively debate on issues of theology.

Serious censorship issues

The seriousness of the issues which The Exorcist addressed was recognised by censors around the world who generally saw no reason to tamper with such an accomplished work.

Despite much press attention focusing on the film's more shocking elements, the Classification and Ratings Administration of the Motion Picture Academy of America granted The Exorcist an uncut 'R' rating which allowed minors to view the film if accompanied by an adult.

As MPAA President Jack Valenti pointed out, The Exorcist contained "no overt sex" and "no excessive violence", a conclusion echoed by the usually cautious Catholic Conference which rated The Exorcist A-IV, an adult classification meaning that the film was "moral, but may offend some [adult] viewers."

In the UK, The Exorcist was granted an 'X' certificate which allowed over 18's to view the movie without cuts of alterations.

Ironically, in 1975, Variety reported that the government censorship board of Tunisia had banned The Exorcist on the grounds that it presented "unjustified" propaganda in favour of Christianity!

Showered with awards

At the Golden Globes, The Exorcist scored four major wins, picking up awards for Best Film, Best Director (William Friedkin), Best Screenplay (William Peter Blatty) and Best Supporting Actress (Linda Blair), while the Oscars generated ten nominations including Best Picture, and two further awards; Best Screenplay (Blatty) and Best Sound.

In box office terms, The Exorcist became the biggest grossing hit in the studio's history, nearly trebling the $34m gross of the studio's previous record holder My Fair Lady in the US alone.