Since his high-profile role in 28 Days Later..., Cillian Murphy has been everywhere. From romantic period drama to heavy-hitting Hollywood franchises, Murphy has rarely played the same character twice. In Neil Jordan's Breakfast on Pluto, Murphy plays Kitten, a transvestite terror-suspect whose epic journey to London in search of his mother is both comic and tragic. FilmFocus caught up with him to find out more...

FF: How did you become involved with Breakfast on Pluto?

Cillian Murphy: I was a big fan of Patrick McCabe's novel, The Butcher Boy, and the film which Neil Jordan made of it. That had a huge, huge impact on me—it was one of those movies I came out of and went straight back in to see again. I was only doing bit parts in the theatre when Breakfast on Pluto [the novel, also written by McCabe] came out in 1998, but I felt it was a wonderful creation and a sort of companion piece to The Butcher Boy. And when I heard that Neil had written a script based on it, I guess I saw the potential for greatness was there and I put my heart and soul into the screen test I did for him.

For anyone interested in the arts, Neil's enormously important: a world director and an Irish director. In Ireland we're great storytellers but we're not that strong visually, and he's the exception. He's a true visionary. That word is bandied around quite easily these days, but he makes intelligent films that won't pander to an audience.

FF: Kitten's quite far removed from anything you've played in the past—did you look at any transvestite movies of the past to help get you ready for it?

CM: No. I'd seen those films in the past, but I didn't use them as research—I admire actors' performances but it would be foolish to look at something and try to impersonate it. There's a long history in film of men dressing as women, but I wanted to have a complete blank canvas and try to invent something new. But I did think Terence Stamp was the best thing in Priscilla, Queen of the Desert. It's easy to fall into the trap of that campy, queeny thing, but he carried it off with such grace—there was a beautiful elegance to him.

FF: So how did you go about researching the character?

CM: I used the book as my primary source and then I spent a lot of time observing women. Neil said, "Go and treat yourself like a lady," which I did. It involved buying a lot of products and getting facials and massages and just thinking about stuff that most men generally don't think about.

I had no reference for the transvestite world, but my agent in Ireland knew someone who knew someone. Trixie was the guy's name—a wonderful man. I found the trannies to be warm, protective people, very smart and creative. I went out with them to clubs in London as a boy on his first night out in drag—the "androge look," as they call it. That's Kitten's look for most of the movie—it's only towards the end that she's in the full regalia. Neil was determined to move away from The Crying Game, where the whole thing was about the revelation that Jaye Davidson [who plays a transvestite] was a man. Kitten is this organic being who happens to be very feminine but is definitely a boy; and nobody can take that away. The character wasn't in any way trying to deceive or pull the wool over anyone's eyes.

FF: How was it when you saw yourself in "full regalia" for the first time?

CM: Kitten was very far away from me but those characters are the ones I most love playing. I really enjoyed wearing drag. I looked at myself and saw a resemblance to my younger sister, who is very pretty. But, with a role like this, you can be beautiful but if you don't have anything to back it up, the audience is going to lose interest very quickly. I'd describe Kitten as wonderfully optimistic, probably the most optimistic character I've ever played. The film itself is a lot more positive than the book, and quite modern in its outlook.

FF: Breakfast on Pluto is set in the early Seventies. You were born in 1976, so what does that decade mean to you?

CM: I'm very much interested in the music of that era, especially the early to mid Seventies, which produced some of the finest modern music we have—like David Bowie or Marc Bolan—and some of the finest film-making. And the clothes are very flattering to both men and women. There's also a lot of trashy music in the film, which Kitten identifies with and attaches great importance to, but that's because of her circumstances.

FF: Kitten becomes involved with an IRA hitman and is present at a London pub bombing—what has been your own experience of Ireland's political violence?

CM: I was at a huge remove from any of the Troubles—they didn't impact on my life other than on the television news. Cork has a massive history of resistance, but that was back in the Twenties. I was very aware of it, obviously, and interested in it, but I wasn't politicised and never ever involved personally.

FF: Still, you have just finished a film with Ken Loach, The Wind That Shakes The Barley, which deals with the guerrilla armies formed to do battle with the British Black and Tan squads in 1919.

CM: It's about, I guess, the genesis of the IRA, and a time when Cork was a hotbed of resistance. It's a very strong story about a small community and a load of young men, farm labourers and university students and shop hands, who drove the English out of Cork in a way that became a template for guerrilla warfare around the world. That story has never ever been told in film or literature because it's still a very touchy subject at home in Ireland. I think the only man who could have made this film was Ken Loach. I can't speak highly enough of him. I shot it my hometown, and stayed with my mum and dad. We were out in the countryside and it was a beautiful summer. It was the one of the most satisfying times I've ever had on a film set.

FF: You've moved, within just a few months, from playing the villains in high-profile Hollywood studio movies like Red Eye and Batman to making low-budget films for Neil Jordan and Ken Loach. Which do you prefer?

CM: You can make wonderful films within a small, independent environment and you can make wonderful films in Los Angeles as well, within the studio system. You hear a lot of actors saying, "I'd never go to Hollywood and sell out," But, if it's a good script and a good director, why not? To shut oneself off completely is, I think, very limiting for an actor.

Acting wasn't a dream I'd had since I was six years of age and, when I started out, I didn't think I was in it for the long run. I was just a total interloper having a blast. Then I realised it was something I could do for a living, and do for the rest of my life, and I got very serious about it. I pick and choose my films very carefully. There's nothing I've done so far that I can't talk about with commitment and passion.

FF: You started out on stage, in the play version of Disco Pigs, which was later made into a movie. Do you have any plans to return to the theatre?

CM: I spent four months in 2004 touring Ireland in The Playboy of the Western World, but I'd be foolish not to take advantage of the momentum I've been getting though the film industry because all those great stage roles are always going to be there.

FF: Having worked with Danny Boyle on 28 Days Later..., you're currently collaborating again on another sci-fi movie, Sunshine.

CM: We've been shooting it in East London for over three months. I play a physicist who travels into space. It's the most complicated technical thing I've ever worked on, with a lot of green screen and wires. I've got a 6.10am pick-up tomorrow morning. But I don't want to complain about getting up early because I'm having the time of my life.