Jake Gyllenhaal In 'City Slickers' (PHOTO, VIDEO)

See the resemblance?

Jake Gyllenhaal, now a star leading man at 30, is actually an old show business pro. The actor, who features in the new sci-fi thriller "Source Code," made his first major big screen appearance as a ten year old in the 1991 Billy Crystal film, "City Slickers."

Gyllenhaal plays Danny, Crystal's gregarious son. It's not a huge part, but he plays an important role, and it would start him on a career path that would get wider with "A Dangerous Woman" and truly open up in his 1999 film, "October Sky."

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