Chris Pratt — Andy Dwyer to Star-Lord

Pratt was the lovable, out-of-shape Andy Dwyer on Parks and Recreation for seven seasons. Then he lost 60 pounds in six months for Guardians of the Galaxy (2014), and the transformation was so dramatic that his audition tape went viral. Guardians grossed $773 million. Jurassic World followed at $1.67 billion. The chubby sitcom guy became one of the highest-paid actors in Hollywood at $20 million per film. His training regimen — documented on Instagram — became its own content franchise. Pratt proved that in Hollywood, the only thing standing between "funny sidekick" and "action hero" is a personal trainer.