Wes Anderson's animation movie Fantastic Mr. Fox, starring George Clooney as the voice of the eponymous hero, got its world premiere on Wednesday on the opening night of the London film festival.

The movie is an adaptation of British author Roald Dahl's popular tale of the same name, and tells the story of how Mr. Fox's animal instincts get the better of him and threaten to disrupt his idyllic family life.

Trapped underground with not enough food to go around, the Fox family and animal friends band together to fight against evil farmers Boggis, Bunce and Bean, who are determined to capture the audacious fox at any cost.

This was actually the first book I personally owned, Anderson told reporters. It was a book I loved as a child and also it introduced me to Roald Dahl's works in general, so it made a big impression on me.

He first approached Dahl's widow about 10 years ago to get the rights to make a movie, and was determined to stay true to the dark side of the original.

I remember being scared by Roald Dahl and I loved that, said the director best known for comedies like Rushmore and The Royal Tenenbaums.

I don't think we made it any darker, but we tried to keep it as dark. It's a movie where they're not in danger of getting hurt, they are in danger of getting killed, and that's the way it is in the book.

TONGUE IN CHEEK

When he read the script, Clooney was unsure exactly what audience Anderson was aiming for, telling the director: I don't know who will see it, though, as it's sort of made for grown ups and sort of made for kids.

Bill Murray, in his trademark deadpan style, spoke of playing the part of badger.

Channeling the badger, he joked. We've all got a little critter in us and when cornered we can fight ferociously and sometimes we burrow deep, deep, deep to get away from all these people and be safe.

When asked what he thought the message of the film was, Clooney replied: Stealing is good.

Anderson adopted classic stop-motion animation techniques rather than computer-generated action, and the work was carried out in East London.

Fantastic Mr. Fox opens in Britain on October 23 and in the United States on November 13.

The annual London Film Festival, which runs for 16 days, is attempting to compete with major international festivals like Toronto, Venice and Cannes. It will screen around 200 feature films, although the majority have already been shown elsewhere.

The festival's closing film, with its world premiere on October 29, is artist Sam Taylor-Wood's debut feature Nowhere Boy, about John Lennon's formative years.