Summer Movies 2012: Rihanna, Cobie Smulders, Diego Boneta And 9 Other Breakout Stars

Before last summer, Jessica Chastain and Michael Fassbender were just a couple of young actors trying to make it in the crazy world of Hollywood. Now -- following the successes of "The Help" and "X-Men: First Class," respectively -- Chastain and Fassbender are both A-listers, working with the likes of Robert Downey Jr., Brad Pitt and Angelina Jolie. Summer movies: where stars are made.

So! Which actors are sitting on the verge of a breakout as this year's crop of summer movies arrives? Allow HuffPost Entertainment to offer you some options. Ahead, 12 potential summer breakout stars -- from Cobie Smulders to Luke Kirby.

PHOTOS: Summer 2012 Breakout Stars

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BEFORE YOU GO

12 Breakout Stars of Summer 2012

PHOTO GALLERY

12 Breakout Stars of Summer 2012

Summer Movies 2012: Rihanna, Cobie Smulders, Diego Boneta And 9 Other Breakout Stars

12 Breakout Stars of Summer 2012

12 Breakout Stars of Summer 2012

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Cobie Smulders ('Marvel's The Avengers')

Best known as Robin Scherbatsky on "How I Met Your Mother," Smulders gets her big-screen break in "Marvel's The Avengers." She plays Maria Hill, Nick Fury's right-hand woman and the expounder of much exposition in the superhero mash-up. Smulders also gets in on the action and wears a skin-tight S.H.I.E.L.D. suit, which isn't a total surprise; after all, director Joss Whedon once wanted her to play Wonder Woman. Make that happen, Hollywood gods.

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