Joaquin Phoenix made his film debut at age 10 in Space Camp, a lighthearted sci-fi flick in which he and a group of campers are accidentally orbited into space. Now in his mid-20s, Joaquin has established himself as a serious actor with a penchant for working with some of Hollywood's top stars. His credits include Parenthood with Ron Howard, Return to Paradise and Clay Pigeons with Vince Vaughn, To Die For with Nicole Kidman and 8MM with Nicolas Cage.

He sees his latest film, Gladiator, as the rarest of opportunities -- even though he's never watched a Roman epic before. "I never had!" he says. "I feel so embarrassed!" Maybe it's not such a bad thing, though. "I had to take my own fresh approach, and I certainly wasn't influenced by any other films of the genre," he says. Joaquin spoke with iCAST about the making of Gladiator, working with director Ridley Scott and the challenge of playing his most complex character yet, the ambitious young prince Commodus.

iCAST: Your performance was very satisfying in Gladiator. What did you think?

JP: Thank you. It was an incredible opportunity, and somewhat rare, to get not only a script that has scenes that are multi-layered and rich, but also to work with a director like Ridley Scott. If you look throughout his films, he's interested in the epic film visually, and a large canvas, but he also values the details and nuances of a human story. And it's so rare for an actor to have that opportunity.

This film has everything for me. I mean, more physical aspects of the character, the sword fighting towards the end. And you don't always get that -- you're either going to be doing the buddy cop movie where you're like, "No!" and running around shooting; or it's a more intimate, character-driven drama. But this film seemed to offer all of those possibilities.

iCAST: There must have been a point where you thought, this is really hard; the vulnerability, the deceitfulness.

JP: Sure. Balancing all of that is difficult. But, you know, I had a lot of help with Ridley. And especially in a film of this size, it can be difficult to maintain focus. How is this scene going to fit in with the previous scene, or the following scene? You need [to be able to ask] a director, "Can I go here? Can I explore this part of the character at this point, or is it giving away too much?" So we always were riding a fine line.

Actors always talk about their characters having an arc throughout a film. But Commodus seems to have miniature arcs within a scene. So it was difficult to balance that. But it's kind of everything you want as an actor. To be honest, you can just get plain bored. I know I certainly have in the past with some roles. So there's this kind of an ideal opportunity.

iCAST: What made you choose this film?

JP: This is a film where there's no reason to not do it. I thought there was that opportunity to try something that I hadn't done before that would be challenging to me, and that would also be hopefully unique and enticing for an audience.

But the chance to work with Ridley, who I've admired for years [was a big attraction]. He actually executive-produced Clay Pigeons, so I had met him before. And he's brilliant, and Russell Crowe, who I just think is this genius actor. There were so many reasons to do this film. I think that's what an actor looks for, the opportunity to embody characters from different periods and different scales of production, be it a small film that's shot in five weeks and under 3 million; or a film of this scale, which took five months. So each process tests you in a different way. And that's certainly what I look for in a film.

iCAST: Have you watched movies in this genre before?

JP: I never had! When you ask me this, I feel so embarrassed! I never had. But I actually am glad that I hadn't. And I hadn't going into production, either. So I kind of had to take my own fresh approach, and I certainly wasn't influenced by any other films of the genre...

iCAST: You should see Spartacus.

JP: Now?

iCAST: Yeah, now. But it's funny, because you're sort of a cross between a character in Spartacus and The Robe.

JP: Can I ask you a really stupid question? Who played Spartacus?

iCAST: Kirk Douglas played Spartacus. But you actually reminded me of Laurence Olivier in Spartacus, especially the way they use your face.

JP: Thank you for that! I really appreciate it.

iCAST: Ridley Scott is very quiet. He's standing there with the cigar, basically in charge of it all. Is that what keeps you going when it gets tough, this feeling that it's okay, that someone's in control?

JP: Absolutely. On a film like this, I can't stress how important that is. He is so patient and so calm. I don't know how he'd do it. He'd have five cameras running, five monitors, hundreds of extras. And he'd be watching all this.

And I know that one of the cameras is just floating between me in the roll box [in the arena] and Lucilla, played by Connie Nielsen. And Ridley would look at it all [using all the different cameras] and I'd just be doing a bunch of stuff. And suddenly the radio would crackle, "Ridley's coming on." And he'd come up and say, "I like that thing that you did, try that again." And I was like, how the hell did you see that? You've got tigers attacking Russell over here, and somehow he's able to just balance all of it, take it all in, and edit in his mind.

And even between takes, they'd be setting everything back up, and he'd be drawing the storyboards for the following day's work, or for the scenes that we were going to do. And they're works of art of themselves. They're beautiful -- the detail. So I really looked for that, especially since it was the first film of this size and caliber for me.

Initially when I arrived on the set, I just looked up and went, "Oh no! What have I got myself into?" I thought it would be overwhelming. But he is so reserved and calm. You just pick up on that, pick up on that energy. I mean, you certainly can feel if somebody seems overwhelmed and frenzied; and it's the last thing you want from a director when they're going into a five-month shoot with a picture like this.

iCAST: Talk about the complexity of your character. Is it fun to play somebody who, from one moment to the next, you don't know is going to cry or just lose it?

JP: It's endless -- the directions that Commodus could go into. It's always fun exploring it. I remember going into this scene, which after is what we called the "Busy Bee" scene, in which I explain, "If his mother so much as dah-dah-dah, he will die..." and this whole kind of thing. I had always wanted Commodus to have this kind of confined rage - so that you were never sure in which direction he was going to go. He always seems to be twitching and boiling underneath. I thought it was kind of the ideal opportunity for him to just lash out and blow his top. And I said to Ridley, "Do you think that's right? I was thinking about just screaming right now here at the end, 'Am I not merciful?' when he reaches the line." And he said, "Yeah, yeah. Try it." So we did it.

So it's things like that that are fun and exciting. When you get to set, there are a number of paths to take with a character. It seemed like the work was never done. We could never do enough to discover this guy.

iCAST: Can you explain how you prepared for the scene with Richard Harris? Working with Richard Harris is quite an achievement as well.

JP: First, the dialogue in and of itself just was powerful. When I first read it, it hit me emotionally. And then I just -- I magnify those moments. And I go away alone, and I just play the dialogue over in my head, over and over. I'm afraid that I can't really do myself justice in explaining the process. But I just tried to get to the root of that pain, of a child's feeling of neglect, and this great regret.

What's important is, he's fighting to hold back this emotion, and yet it's finally this confrontation. I always imagine that the speech that he has is something that he's said in his head a thousand times in his fantasy, talking to his father -- as if it's something he always wanted to say. And then suddenly he has the opportunity. But there's almost this reluctance and this fear to give in. And finally, the emotion just becomes so overwhelming, and it's just this sudden outpouring.

iCAST: Did you have to gain weight for this role?

JP: No, I put on weight. Initially I thought that I wanted to be built, muscular, throughout the course of the film. So first, leading into pre-production, I worked out for a couple of months, just eating a lot, putting on weight, and getting more muscular for a lot of fight scenes. And then once I became Emperor -- we shot somewhat in sequence, suddenly I was like, "Oh, fuck all that! I'm not going to the gym!" And I started eating a lot. I wanted him to put on weight. I wanted to try and show this decadent nature, and I thought it would help me age a little bit. Because in the beginning of the film, I really wanted him to be the young prince in waiting, and there's something more disheveled and scraggly about him. Like, I had my hair permed twice.

And then as he becomes emperor, I just wanted to alter his physical appearance, because you leave that story for a few months, and it's Russell's journey. And when you come back, I thought it was really important to alter his physical appearance as much as possible. So at that point I put on some weight. I don't know if you noticed, but there's this fabulous Roman bloat that I had.

iCAST: And you're a vegetarian, aren't you? So what did you eat?

JP: Pasta! And also if you have vodka before bed, like three times a week, it helps a lot.

iCAST: What was it like being with the cast after hours?

JP: It was this little community. We shot in Malta, and it's an island. And we called it The Rock, because we just felt imprisoned. There was nowhere to go. The first week, you go all over the island -- that's it. So we'd all just get together every night after work and talk, play backgammon. But mostly, we just had political debates. Derek Jacobi and I just started those. But he was really interested in an actor's responsibility, if any, for political causes. So we used to get in these big table discussions -- of which I won't share any with you! [Laughter].

iCAST: Do you feel now that you are more comfortable working on films of this size?

JP: Yeah, certainly. In many ways, this was the icebreaker. But, you know, honestly, I go into every film petrified. There's so much riding on it. And once you're done, it's done. It's in the can. There's nothing you can do about it. And it's overwhelming. Once you get into the wardrobe and you get on set, you really forget about how much money is being put into your production. It's just you and the director and the actors.

iCAST: That's the part that you enjoy, the intimacy?

JP: That's all I want. That's all I'm after. The process is what interests me the most. Ridley and I would sit between setups, and I'd just stay on set all day long, and just talk to him, and pore over the script. And there's nothing more exhilarating. It's kind of the greatest high in the world -- to discover something new about the character that you hadn't seen. It's just that moment where the light bulb goes off in your head, and you go, "Oh my God, yes! We could play it like that. This would be really interesting if we..."

It's kind of endless. In the scene with Connie Nielsen, where I talk about a father's dream, "Life, it's a dream, a frightful dream." And at the end of that scene, it kind of ended as a number of the other scenes had ended, with me saying, "Stay with me tonight." And she said no and walked away.

And all three of us were trying to find a more interesting version of that scene. So we came up with laying her down on the bed, talking during this whole thing. She feels very sympathetic towards my character. And I lay her down, and go in for the kiss. We called it the Abort Mission scene, because as I went to kiss her, I just decided no, because it's not really what Commodus wanted. His sexual desires were just masking his true needs.

And so that kind of thing, it's just rare. And it's so exciting to take a scene in a completely different direction. I mean, we absolutely altered what that scene was, and what an audience would have walked away feeling, had it stayed in its original condition. There's nothing quite like that. That's what I love to do.