Hugh Jackman's extreme diet

Hugh Jackman went without water for 36 hours before filming the opening scene in 'Les Miserables'.

Related: Hathaway says 'Les Mis' made her deprived

The Australian actor takes on the role of Jean Valjean in the big screen adaptation of the hit musical and he admits he had to go to extreme measures to look like a starving prisoner at the beginning of the movie before piling the pounds back on as Valjean made a success of his life on the outside world.

Related photos: 'Les Miserables' premieres in London

Speaking at the world premiere of 'Les Miserables' at London's Odeon Leicester Square cinema, Hugh told BANG Showbiz: "I had to lose a lot of weight, so I went on a very strict diet. I even went without water for 36 hours before I filmed the opening scene. And then after that, I put on weight. I was training every day."

In the movie, Russell Crowe plays Valjean's arch-enemy, Javert, and Hugh said he loved every moment of working with Russell, especially as they have a lot of history together.

He said: "I've known for Russell for years. If you ever go to a party thrown by Russell you end up singing so we had a lot of practice! But it was great working with him and he's one of the world's greatest actors. I love him."

Other stars to walk the red carpet at the premiere included Anne Hathaway, Amanda Seyfried, Eddie Redmayne, Helena Bonham Carter and Sacha Baron-Cohen.

'Les Miserables' is released in the US on Christmas Day (25.12.12) and around the world on January 11 2013.

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