Chris Evans' rise as Steve Rogers in Captain America: The First Avenger demanded more than super solider serum.

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While Marvel Studios clearly had ideas about heading towards The Avengers when they set about making their own films starting with Iron Man, it wasn’t until their fifth film—Captain America: The First Avenger—that they were making a movie while The Avengers was rocking and rolling and getting geared up to start production. Not only that, but the 1940s-set Captain America would serve as the audience’s lead-in to the experimental The Avengers, and thus needed to tee up major plot points while also introducing a major new superhero. And while the end result works wonderfully, …