Sony Pictures, the studio behind the film starring Tom Hanks and Sir Ian McKellen, is reported to have been so concerned that it has consulted Catholic and other Christian specialists on how it might alter the plot of the novel to avoid offending the devout.

Film officials have held talks with Catholic groups and other organisations despite Dan Brown, the author, insisting that “it’s only a novel and therefore a work of fiction”, The New York Times reported yesterday.

The Catholic League is calling for Ron Howard, the film’s Oscar-winning director, to include a disclaimer acknowledging that the movie is fiction.

The Da Vinci Code, which is being filmed this summer with locations including Winchester Cathedral and Rosslyn Chapel, near Edinburgh, is based on a novel that has sold 25 million copies worldwide. Among its more controversial claims is that Jesus married Mary Magdalene, a former prostitute, and that she bore him a child. This has been denounced as virulently anti-Catholic and a risible hoax.

Opus Dei, the Catholic organisation, is particularly concerned about its own depiction, because it is a central villain in the book. Its members are depicted acting unethically for the sake of God, the Church or Opus Dei, whereas the organisation is a Roman Catholic institution that adheres to Catholic doctrine and condemns immoral behaviour.

“The novel portrays Opus Dei in a completely inaccurate way,” Brian Finnerty, a spokesman for the group, said.

“We wrote to the studio, expressing our concern. They sent back a reply that was polite but non-committal; but Opus Dei is completely unlike the portrayal in the novel.

“It is about ordinary people trying to find God, not about searching for the Holy Grail. It’s ordinary Catholics trying to come closer to God in their day-to-day activities and it is a mainstream part of the Catholic Church. It’s been blessed by all the Popes since the earliest years.”

The studio has been asked to consider whether the central premise — that Jesus had a child with Mary Magdalene — could be more ambiguous and whether the name of Opus Dei could be removed.

Condemnation of the book has been widespread. Last month the Roman Catholic Church in England and Wales denounced it as logically and historically flawed. In March the Vatican appointed a top cardinal to rebut what it dismissed as lies, distortions and errors.

Carl E Olson, a Catholic and co-author of The Da Vinci Hoax, a book rebutting the The Da Vinci Code, predicted that many religious people would be offended unless the film bears a pale resemblance to the book — which, he accepts, would risk alienating fans.

Dismissing the novel as “trash” and “poorly written”, he said that its historical claims could be torn apart.

Sony declined to comment

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