Most of the time being a Hollywood actor is all about the glitz and the glamour, but occasionally actors have to go that extra mile to transform themselves for a role. Take a look at some of the most dramatic actor transformations ever seen on film.
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Warner Bros. Pictures
Butler and other actors who appeared as the fearsome Spartan warriors in the movie "300," underwent a four-month training regimen that gave them those defined six-pack abs and toned, muscled bodies. The sessions with trainers Franco LiCastro and Mark Twight, who created the "300-rep Spartan workout," would reportedly last up to six hours.