The Trojan prince hoping to bring Achilles to heel...

Four years ago, Eric Bana was a semi-famous stand-up comic in his native Australia. Then came his breakthrough role in Chopper, a part that led to The Hulk and then to Hector in Troy. But did Bana realise that a small indie film about an unsavoury crim would send him rocketing into the media limelight? "Well, I really felt that I could do the role, but you'd be kind of crazy to think that it would do what it has done. You'd be certified insane," he says on Troy's Mexico set.

Which is ironic, as that's exactly what heppened to the real-life Chopper. But the 35-year old Bana, the son of a Croatian dad and a German mum, is only crazy in the way he prepares for his parts. "I like to work in a very non-linear fashion," he explains, "so my references are bizarre and not always obvious. But I don't like to discuss them because you'd probably think I was a bit crazy."

For Hector, a noble hero, Bana has, as with Chopper, had to pile on the pounds. Although this time, they're muscular pounds. "I've always been pretty active but this film is an endurance test, it's unbelievably physical," he says. "I have to do a hell of a lot of fight choreography training, the there's the gym and training with the stunt guys. It does take a lot of personal discipline to stay sane and positive." So it's just as well that Wolfgang Petersen is running the show - "The best-humoured person on the set every day," according to Bana. "I'd put him in the same category as Ridley Scott. You can't even say that he's good at handling the pressure because I don't think that he even acknowledges that there is any pressure." Pressure is something Bana himself is used to from last summer's biggest gamble, pressure that eventually saw The Hulk tagged as a commercial failure. Bana, however, remains as belligerent as Hector: "It's not like it was a flop. When you're on a long shoot it is a long personal investment. If I wasn't happy with the end result I'd be bloody upset, but in every case so far I've been happy. Troy could take $50 and I wouldn't regret it. I've had the best time of my life."