Colin Firth's 'Railway Man' Portraits at the 2013 Toronto International Film FestivalLarry Busacca/Getty Images

Colin Firth has always been sexy, but now he can add "seriously svelte" to the list of adjectives used to describe him.

During a red carpet appearance with co-star Reese Witherspoon at the Toronto International Film Festival premiere of their movie "Devil's Knot," Firth showed off his recently slimmed-down physique. The actor had shed some weight for another TIFF movie, "The Railway Man," in which he plays the older version of a British soldier who's taken prisoner by the Japanese in World War II and forced to work on a railroad connecting Thailand to Burma.

Reese Witherspoon and Colin Firth at the 2013 TIFF Premiere of 'Devil's Knot'FilmMagic

Firth, who won the Best Actor Oscar for his work in "The King's Speech," has spoken previously about the importance of embodying his characters physically when preparing for a role.

"Some people spend days, weeks even, getting inside a character, getting under his skin, working out how he thinks, what makes him tick," Firth said, according to the Daily Mail. "My secret is that I get outside the character. Take my character in [the 2009 film] 'A Single Man': it's the big glasses that draw you in, make George's anguish believable."

"The Railway Man," which co-stars Nicole Kidman, debuted to a standing ovation at the festival on Friday. It is currently seeking U.S. distribution, and may not make its stateside debut until sometime next year.

[via Daily Mail, THR]

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