SINCE its publication by Edinburgh's Canongate in 2001, The Life Of Pi has won many friends, from the Man Booker judges to President Obama, who found the tale of a boy all at sea with a tiger "an elegant proof of God, and the power of storytelling".

Perhaps the most powerful pal of all to Yann Martel's novel, however, was another president, this one of Fox 2000 Pictures. It was Elizabeth Gabler, pictured below, who bought the rights in 2002 and was determined to turn a book most thought unfilmable into a movie. Ten years of hope, sweat and technical advances later, she has succeeded. The fantasy drama, directed by Ang Lee, opens in the UK next Thursday.

"I thought it was a fascinating story," says Gabler, speaking from her office in Hollywood. But as much as she loved it, even she wasn't sure at first whether the book could be turned into a successful film. "It was one of those greatly challenging pieces of literary material. I just thought, well, this would really take a very special filmmaker's vision to bring it to the screen."

The Life Of Pi is the story of young Piscine Molitor Patel, Pi for short, who leaves India for Canada with his family to start a new life. With them on the voyage are the inhabitants of the family zoo, including one Richard Parker, a Bengal tiger, who acquired his not so exotic name after a paperwork mix-up. Following an accident at sea, Pi and the tiger end up in a lifeboat together. Both are terrified, but only one has the ability to bite the other's head off.

After Martel gave his consent to a film, a screenplay was commissioned. It was still too soon, however. "At the time technology just didn't really afford us the opportunity to make the movie in any sort of way that was basically do-able. They didn't have the capability to do the furred creatures the way they do now." Since Richard Parker is as much a character in the film as Pi, the animal had to be seen to have emotions.

Along came Aslan in The Lion, The Witch And The Wardrobe, and computer-generated imagery in general began progressing by cat leaps and bounds. The next job was to find a director. Gabler heard Lee was interested. Eight months later, all the while pondering how the film could be done, he said yes. "It was really about finding the right filmmaker for the property," says Gabler, "the person with the vision and the capabilities to bring it to life."

She was drawn to Lee – the director of Sense And Sensibility, Crouching Tiger, Hidden Dragon and Brokeback Mountain - because of his track record of innovative filmmaking. "He has made movies in so many different genres and he has succeeded with very difficult subject matter and made it into commercial films." Pi is Lee's first film in 3D.

With a director in place, a screenplay by David Magee (Neverland), and the right technology to hand, a Pi had to be found. Some 3000 hopefuls were auditioned around the world. True to the spirit of serendipity that runs through the book, Pi was found by chance. Suraj Sharma, a 17-year-old student, had only come along to the auditions to keep his brother company (and on the understanding there would be a Subway sandwich afterwards). He was persuaded to have a go and got the part. There was just one not-so-small problem when it came to playing a boy all at sea – Sharma could not swim. He was given lessons, and ended up doing all his own stunts.

Gabler became president of Fox 2000 Pictures, part of Twentieth Century Fox Filmed Entertainment, in 1999. After graduating from the University of California, Santa Barbara, with a degree in English literature, she worked for a talent agency before entering the film business. Now 56 and married with one daughter, Gabler is the kind of studio executive everyone with a film pitch wants to please. This is a woman with her finger on the green-for-go button. At any one time, Fox 2000 will have 75 projects in development, 30% of which will make it to the screen. Gabler's reputation as a picker of box-office winners – The Devil Wears Prada, Cast Away, Rain Man, Marley & Me, Alvin And The Chipmunks, to name but a few –undoubtedly helped overcome reservations about turning Life Of Pi into a movie. How does she know what is going to be a hit? "First and foremost I ask myself is that something that would get my attention, is that something that I would want to go and see, is that an idea for a movie that would make me say: 'Oh I have to go out of my house and buy a ticket and sit in a theatre and watch this film'? That's the first thing. The other part of it is, is it a unique story? Does it have something emotional to bring to the audience?"

One of her biggest gambles was the story of a desperate dad who puts on a frock to get close to his children, a picture otherwise known as Mrs Doubtfire.

"It was basically a black comedy that told the story of how children cope with divorce. I thought the idea of this dad dressing up like a nanny was hilarious. The only person I ever thought could do it was Robin Williams. He created the character, Scottish accent and all, and the whole character, the whole movie, came to life. That was a big, relatable idea for kids, for parents, for everybody."

When she worked at United Artists, one of the consultants was the legendary director Billy Wilder. "He was basically a mentor of ours, he would read our screenplays and give us his thoughts. He was a wonderful man, very talkative, loved to tell stories of his life and work. One of my favourite things that he would say when people would ask to remake one of his movies was, 'What, didn't I do it right the first time?'"

Hollywood has traditionally been seen as a company town where the business is movies and those in charge of making them at the highest levels are men. But things are changing, believes Gabler. "There are a lot of women in positions of power. If you look around the Hollywood landscape, in every division at Fox there's a woman president, Amy Pascal is co-chairman of Sony, Donna Langley is in a very senior position at Universal, Stacey Snider is head of DreamWorks."

As for Life Of Pi, it opened in the US in November. So far, according to the latest Box Office Mojo figures, it has grossed $167m (£103m), $61m (£37.8m) in the US, and it is just about to open in many more countries.

Nice to know she was right then? Gabler laughs. "It was good to know. I had a feeling and I had a lot of hopes, but you never know. You can always be surprised either way. It's never been anything I like to take for granted."

Life of Pi opens on December 20.