When Eddie Redmayne heard there was going to be a film version of Les Miserables, the British actor knew he was destined to play the dashing battle hero Marius.

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"I was doing a film called Hick with Chloe Moretz and Blake Lively. We were shooting in North Carolina," the 30-year-old actor tells senior reporter Charles Thorp in the Dec. 31 issue of Us Weekly. "I sat in my trailer, dressed as a cowboy, and sang! Saying it now it seems really odd, but when I was there it made perfect sense to audition that way."

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The London native, who first saw the stage show when he was 7, taped himself belting out the musical's "Empty Chairs and Empty Tables" and sent it to his agent, who then mailed it to the film's producers. "That was the start of what become like an American Idol, X Factor-style audition," the actor says. "It was so intense -- I have new respect for people of those shows. The only thing missing was Paula Abdul and Simon Cowell!"

Redmayne -- whose previous film credits include My Week with Marilyn, The Other Boleyn Girl and Elizabeth: The Golden Age -- plays the love interest to Amanda Seyfried's character, Cosette. "She's like this amazing ball of light and that's exactly what the part needs. Les Mis is fairly dark at moments, and when she comes on screen, everything just lights up," Redmayne raves of his 27-year-old costar. "It was nice being with her in London, getting to hang out with her."

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The theater vet was in awe watching costars Hugh Jackman, Russell Crowe and Anne Hathaway show off their singing chops, he tells Us with a laugh: "Nothing was more entertaining than seeing Wolverine, Gladiator and Catwoman do vocal warm-ups!"

This article originally appeared on Usmagazine.com: Eddie Redmayne Compares Les Miserables Audition to American Idol Tryouts