Centurion's writer/director Neil Marshall kept an open mind about who might play the roles in centurion prior casting. He wanted to concentrate fully on writing the characters. Even so, Michael Fassbender was attached to the lead part of Quintus Dias very early on.

"We stuck with him and he stuck with us and it was really question of belief on both parts", confides Marshall. "I totally believed that he could carry the part off and he believed in us making the film that we set out to make".

The part of Quintus intrigued Fassbender: "We know that Quintus' father was a famous gladiator who won his freedom in the Coliseum. I thought that was quite interesting: somebody who lives in the shadow of his father, and feels like he's got a lot to prove. He basically volunteers for the post in Briton to prove himself. As the film progresses, he's thrown in a position of command. I thought it was quite interesting to play with his doubts and the journey of the man; how he actually steps up to the plate and takes command. We know at the beginning he’s very much for the ethos of Rome; he totally believes in it. As the film moves on he becomes disillusioned with the Roman Empire."

But alongside the interesting personal and political journey of his character, Fassbender also relished the opportunity to be involved in all action movie. "Neil's unashamedly going towards that adventure theme genre, which I really like. You know, he doesn't sort of get stuck in what would apparently be a British film. He just goes with his inspirations, which are a lot of action and adventure films."

"Michael brings a huge number of qualities to the role" says Producer, Robert Jones. "I mean, he's a fantastic actor as we've seen in other films like, most recently, Steve McQueen's Hunger, and Quentin Tarantino's Inglourious Basterds. He can ride and he can fight, so he's not just in it for the acting. He enjoys the action."

"I think what makes Michael so great." Says Marshall, "is that he's fearless. He will pretty much try anything. He isn't afraid to run through the snow half naked or whatever. There were never any complaints. He was utterly professional throughout."

Indeed, it fell to Marshall and Jones, to rein Fassbender in on occasions. "I had to hold him back, actually, from doing his own stunts a lot of time. He wanted to do the riding through the fireballs; he wanted to jump off the cliff into the river, which was a really dangerous stunt. He would say, 'Let me do it. I'd love to do it."

Marshall has no doubts his faith in his leading man was repaid handsomely. "It worked. I mean, it was a fantastic working relationship and he delivers a storming performance."