Journalists gave eagerly awaited film "The Da Vinci Code" a cool reception at its first press screening on Tuesday, a day ahead of the world premiere of the adaptation of Dan Brown's controversial novel.

The release of the big-budget Hollywood thriller has already prompted a wave of protests from Christians across the world who believe the theories put forward in the novel are blasphemous.

One of the central characters suggests Jesus Christ married Mary Magdalene and they established a dynasty which elements within the Church would stop at nothing to try to cover up.

The outcry from religious groups in India, the Philippines, South Korea and the United States among others has made the film one of the most controversial releases since Mel Gibson's "The Passion of the Christ" in 2004.

The Vatican has led the offensive against The Da Vinci Code, calling for a boycott and even unspecified legal action against both the book and film.

While the protests have provided studio Sony Pictures with the kind of publicity money can't buy, the reaction at the first press screening in Cannes was largely negative, and loud laughter broke out at one of the pivotal scenes.

"Nothing really works. It's not suspenseful. It's not romantic. It's certainly not fun," said Stephen Schaefer of the Boston Herald.

"It seems like you're in there forever. And you're conscious of how hard everybody's working to try to make sense of something that basically perhaps is unfilmable."

But as one member of the audience pointed out, if every one of the 40 million or so people who have bought the novel go and see the film, The Da Vinci Code will be a commercial hit.

The movie industry will be watching The Da Vinci Code's performance closely after the first two summer blockbusters -- "Mission: Impossible III" and "Poseidon" -- failed to deliver the Hollywood Grail of box office success.

Earlier on Tuesday Da Vinci Code stars including Tom Hanks and Audrey Tautou, and the normally publicity-shy Brown, were greeted by hundreds of fans and journalists when they arrived in Cannes on a train decorated with a giant Mona Lisa.

Hanks will be joined by a host of Hollywood 'A'-listers in the glamorous Riviera resort as it gears up for 12 days of promotions and parties on the palm-lined Croisette waterfront.

PROVOCATIVE LINEUP

Away from The Da Vinci Code, Cannes this year promises a mix of political fireworks, sexual experimentation and blockbuster thrills worthy of the world's biggest film festival.

Other major U.S. productions include "X-Men: The Last Stand," starring Hugh Jackman and Halle Berry, and the animated "Over the Hedge," with Bruce Willis providing voice-overs.

Spanish veteran Pedro Almodovar is back with "Volver," starring Penelope Cruz, and U.S. film maker Sofia Coppola presents "Marie Antoinette," with Kirsten Dunst playing the reviled young queen as France spirals toward bloody revolution.

As well as escapism and history there is plenty of politics, with Richard Linklater's "Fast Food Nation" aiming to spoil the appetites of the big fast food chains and Italian production "Il Caimano" satirizing outgoing prime minister Silvio Berlusconi.

Oliver Stone showcases 20 minutes of his upcoming 9/11 film "World Trade Center," French director Rachid Bouchareb examines the forgotten role of Arabs in defending France during World War Two and his countryman Bruno Dumont promises to provoke with "Flandres," set in an unspecified war.

Britain's Ken Loach tackles the early days of the fight for independence in Ireland, and former U.S. vice president Al Gore talks about global warming with "An Inconvenient Truth."

Sex hits the screen with John Cameron Mitchell's "Shortbus," except the buzz is that this time it is real, not simulated. And "On Ne Devrait Pas Exister" by French porn star HPG focuses on a porn actor who wants to break into traditional cinema.