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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Revolution Studios
Sylvester Stallone has kept up his famously muscled physique even as he's aged, as he's shown in recent movies, including 2006's "Rocky Balboa."