Bruce Willis made his name saving the world in movies like the Die Hard series, but between sparkling moments in Pulp Fiction and The Sixth Sense, attempts to shed his dirty-vested image have met with mixed results. His last film, black comedy The Whole Ten Yards, went straight to video. Perhaps then it's not surprising that Hostage sees him back in action-man guise. Still the actor is keen to emphasise that this flick is about more than just the body count.

Robert Crais' book seems to lend itself quite easily to a movie, but what drew you to the story when you read it?

It's a really complicated novel. Turning the novel into a film was a big opportunity for me to make a movie that had some action and that was also a psychological thriller that wasn't 'A Bruce Willis Movie'. Because of the success of a couple of films I've done, like the Die Hard series and Armageddon and things like that, I've saved the world six or seven times now, so I think that audiences have expected me to win and save the day and this story was about a guy who doesn't look like he's going to win. It looks like he's going to lose. The director Florent Emilio Siri and I worked very hard at constructing a story that had multiple obstacles in it, both emotional psychological and physical obstacles.

Whose idea was it to have your daughter [Rumer Willis] in the movie?

It was my daughter's idea to ask to be in the film. In years past all three of my kids have appeared in films with their mom [Demi Moore] and myself. In this film I insisted that Rumer come in and audition for this part. I said, "I'm not going to give you this part, you have to earn it." So she came in and auditioned and won the part. It was a great audition.

Did having Rumer there help you to realise the anguish of what your character goes through when his daughter is taken hostage?

You bet. It just took that whole storyline to a much more emotional level. I think that I got to some places emotionally that I might not have been able to get to if I was working with another actress that was not my daughter. All I had to do was think about any one of my kids being held hostage and you had to dry me off. It is an emotional movie and I think that anyone that has kids can relate to having one of your kids snatched. Not only that but the logline of the film is, "Would you sacrifice another family to save your own?" which is a difficult dilemma on its own.

You've taken your shirt off many times before, but how did you feel about doing that again for the van scene?

I was reading the script saying, "shirt on, shirt on, shirt on, ah, shirt off..." so I had to go and work out and get myself in shape because nobody wants to look like - and no offence to the other guy... but nobody wants to look like the other guy in the van. Nobody wants to look like that on film! I turn 50 this month and I just felt...… I hate working out. Because I work out solely for movies I just come to associate it with work. I did a film with Robert Rodriguez called Sin City where again I had to be completely naked and hung by the neck, standing on my tiptoes on a glass coffee table - it was shot tastefully so the good parts won't be seen! So I had to stay in shape for that, but as soon as that shot was done I stopped working out. That was almost a year ago now so I've let myself fall apart.

Presumably you'll have to get back into shape for Die Hard 4.0...

Ah, Die Hard 4.0. You know I just did about five days of work for a film called Alpha Dog, directed by Nick Cassavetes, and I had to do what would have been, ten or 20 years ago, a really simple stunt. I had to run and get away from the Feds and in one move climb over a six-foot concrete wall and hop down and land on the sidewalk. It was the first time I ever thought, "Oh, I don't know about this. I could fall and land on my ankle and turn my ankle over, or break a bone..." I actually took pause and then to make matters worse, the character that I'm playing in Alpha Dog is a real-life guy and he was there and Nick said, "Jack, show Bruce how to go over the wall!" And this guy just hopped right over the wall - perfect! - so no pressure on me, right? I embarrassed myself, but I'm okay. But jumping off the roof of Nakatomi Tower? Those days are done.

You said a while back that you never wanted to do an action movie again. What changed your mind?

This film solved the puzzle for me. It was widely reported and very misquoted, but what I really meant when I said that was that I was going to take a break from action movies. Anyway what we call action movies now are nothing more than what they used to call cowboys-and-Indians movies, then they called them gangster movies, then they called them WWII movies and Korean war movies and Vietnam movies and cops-and-robbers. It's all just stories about good triumphing over evil. And look, this goes back to the Greeks. They were telling the same kinds of stories and Shakespeare was telling those stories. That's what these films are and when I did the first Die Hard and Mel Gibson did the first Lethal Weapon we both set templates for the modern version of good guys versus bad guys.

Over 15 - 20 years that kind of got done so much - I did three of them and Mel Gibson did four - it just got bastardised. They ran so many by me that I said "no" to and other people turned into films. It was Die Hard on a plane, Die Hard at the White House, Die Hard at a Delicatessen, Die Hard everywhere! I just got sick of it. I got sick of running down a street with a gun in my hand going, "NOOOO!" So I needed to take a little break and what I also said, that got reported less, was that I thought it was time for the genre to reinvent itself and for the stories to get a little smarter and I really think Hostage is a smart story. I don't really see it as an action film. It's more like a psychological thriller. And wait till you see Sin City. It is going to blow your mind!

Hostage is released in UK cinemas on Friday 11th March 2005.