Jeremy Irvine agreed to endure waterboarding torture while filming 'The Railway Man'.

The 22-year-old actor - who stars alongside Colin Firth in the film about a real-life World War II hero - opted to re-enact the terrifying torture method, which dates back to the 16th century and involves water being poured over a cloth covering a captive's face causing them to experience the sensation of drowning.

Jermey refused to fake the pivotal scenes, or use a stuntman to do the shot involving his character Eric Lomax, who became a prisoner of war after being captured by the Japanese and forced to build the 'Death Railway' in Thailand.

He told the Daily Mail newspaper: ''I said: 'Go for it, OK? No stand-ins, no faking.' We rehearsed how we were going to do it, and I was controlling it all the way through.''

''It was bloody unpleasant, but I knew I wasn't in any danger, but I felt it was important that I convey the hell Eric went through.''

I was water-boarded for seconds at a time, over the course of two days, while the real Eric Lomax had to endure the real thing, time after time.''

''It had to look as real as possible. The older Eric is played by Colin and to make sense of the trauma Eric experienced later, it was vital that he be seen to suffer through this awful torture,''

Director Jonathan Teplitzky, praised the actor's decision after making clear the stunt was optional.

He said: ''[Jeremy] didn't have to do it but it makes the scene all the more authentic, and it's crucial to us understanding what Eric Lomax and his fellow soldiers put up with. It haunted them for the rest of their lives.''

'The Railway Man' opens in the UK on January 3, though it's being held for US release in late 2014.