The Wall Street Journal: The roles you've played outside of Harry Potter don't have much in common with the boy wizard. Are you consciously looking for parts that are a departure from the role you're best known for?
Daniel Radcliffe: Realistically, if another seven-film fantasy series came along tomorrow I probably wouldn't do it. I don't think that would be the smartest career move in terms of separating myself and having people see me as an actor as opposed to a character.
WSJ: The role you play in "My Boy Jack" is that of a young solider during World War I. What drew you to that role?
Mr. Radcliffe: I have always been kind of fascinated by World War I. I had a conversation with a friend the other day about how we periodically get depressed about it. I find it a very affecting topic. The imagery that came out of it from the poets and writers at the time has really stuck with me.
WSJ: Anyone in particular?
Mr. Radcliffe: I've always had a love for Wilfred Owen and people like Isaac Rosenberg and Edward Thomas. [Mr. Thomas] is sort of more about England during that period but it's very affecting. It's those kinds of things and books like Sebastian Faulks's Birdsong.
When I did go into the trenches that had been made for the film, there was mud and rats and it was horrendous. I got in there and thought, 'How could anyone possibly live like this?' That was what was amazing to me -- what lengths human beings can push themselves to.
WSJ: You starred in the London revival of the controversial play Equus, about a boy who has a religious and erotic obsession with his horses. Were you nervous about the nudity in the play?
Mr. Radcliffe: It wasn't a huge concern. It's one of those things where you think, I signed up to do it and it's in the script, so just get on with it and do it. Though it is a bit nerve wracking the first couple of times.
WSJ: Your character in "My Boy Jack" enlists in the military at 17 and is forced to grow up quite quickly. Can you relate to that as a child actor?
Mr. Radcliffe: I think the difference between myself and Jack in that respect is that I grew up in an age where the idea and the concept of "teenager" existed. When Jack was around, it really didn't. You were either a child and in school, or an adult. And there was nothing in between really... But there are similarities in that we both had to grow up slightly faster than would be expected.
…I think in America you produce a very special breed of child actor. I see these kids at nine and ten and they're amazing, some of them. And I don't know how it happens. Dakota Fanning, for example… if she were physically older, she could sort of play anything. I didn't have that maturity at that age. In England, if you're a child actor, I think people don't expect you to be able to do it past age ten. It comes as a surprise if you're really interested in doing it aside from just getting rich or whatever.
WSJ: You're still just 18. Are you convinced that acting is what you want to do as a career, or are there other fields that interest you?
Mr. Radcliffe: There are plenty of fields I'm interested in, but acting is certainly the focus for me. Hopefully, people will do as they've done so far and keep giving me that chance to do that. I'm also very interested in writing.
WSJ: Really? What kind of writing?
Mr. Radcliffe: Poetry, mainly. I've written about 150 [poems] now and I love it. I've been doing it for about a year and a half and it's a massive release. As an actor, you do have a certain amount of creative outlet, but filmmaking is a thing that's done by committee and there's a lot of people with a lot of input. With poetry, it's different.
WSJ: I hear you're also a big music fan, too. Do you perform?
Mr. Radcliffe: I tried to play bass. I was rubbish at it -- it was really annoying. I learned bass for about a year and a half... I did actually have one lesson with [Harry Potter co-star] Gary Oldman. He's a pretty accomplished bass player himself and it was one of the highlights of my life. Then I got to the point where I thought, I'm not actually getting better.
WSJ: What types of film roles are you being offered these days?
Mr. Radcliffe: Right now it's very tricky because of Potter. I don't have a spare moment to make something until at least 2010 somewhere. I do the sixth Harry Potter…then I'm going to have a break, then I'm going to New York to do "Equus" on Broadway, which will be great. Then I'm going to do "Harry Potter 7" and by the time that's over I'll be 100 years old. I'm just kidding.