With a few months left in 2011, it’s hard to guess which films will be dominating award shows and top ten lists. So far, my favorites include “The Tree of Life,” “Drive,” and “Moneyball,” but there are plenty of promising films yet to be released. What I can say with certainty, regardless of what happens over the next few months, is that the following four actors will stand out as 2011’s biggest stars. Two of these people are genuine “break-out stars,” while the other two simply had, by far, the best years of their careers so far.

Jessica Chastain
It’s understandable if this name is still unfamiliar to you –Jessica Chastain hasn’t quite reached household name status. She has, however, delivered six widely acclaimed performances in one year. In 2011 alone, Chastain starred in “The Tree of Life,” “The Help,” “The Debt,” as well as the upcoming “Take Shelter,” “Wilde Salome” and “Coriolanus.” I adored her in “The Tree of Life” and her presence elevated “The Help” and “The Debt” beyond uneven writing. “Take Shelter,” co-starring the excellent Michael Shannon, has garnered a lot of buzz following its Critic’s Prize win at the Cannes Film Festival. As Mindy Kaling (“The Office”) humorously tweeted: “It’s the era of Jessica Chastain and we’re just living in it.”

Ryan Gosling
Ryan Gosling has been a known entity since 2004 when he starred in “The Notebook”—a career-defining role that doesn’t do him justice. Seven years later, he’s come a long way. Gosling already proved his considerable skill in films like “Lars and the Real Girl” and “Blue Valentine,” but the release of “Crazy, Stupid, Love.,” “Drive” and “The Ides of March” this year cemented Gosling’s position as a captivating, versatile lead actor. His cocky-but-vulnerable character was the most consistently appealing part of “Crazy, Stupid, Love.,” which is no small feat when you’re in a film with Steve Carrell and Julianne Moore. And whether or not you liked the stylistic choices in Nicolas Winding Refn’s art action film “Drive,” you almost had to respect Gosling’s quietly hypnotic performance as the unnamed protagonist. I have yet to see “The Ides of March,” but Gosling is said to be at the top of his game in that film as well.

Melissa McCarthy
Fans of television’s “Gilmore Girls” have known Melissa McCarthy for a while, but it wasn’t until this year’s scene-stealing turn in box office hit “Bridesmaids” that McCarthy reached the mainstream audience. In “Bridesmaids,” McCarthy added several organic layers to a character who, in the hands of a lesser actor, would have been a walking fat-joke. The subtlety and depth McCarthy exhibits in one key scene remains the most memorable part of the movie for me. Cementing 2011 as her break-out year, McCarthy recently won an Emmy for her sitcom “Mike and Molly.” I hope McCarthy has a long future of roles worthy of her talent.

Emma Stone
No longer known as “that girl from ‘Superbad,’” Emma Stone became a full-fledged star this year due to her outstanding work in “Crazy, Stupid, Love.” and “The Help.” Stone’s funny, relatable onscreen persona reached new heights in these two films, the latter of which also showed off her considerable dramatic talent. Even in unglamorous performances, Stone manages to be funny, attractive and endearing.  She also had a supporting role in this year’s better-than-expected “Friends with Benefits,” but her work in “The Help” was likely her most impressive to-date and she more than held her own with Gosling, Carrell, and Moore in “Crazy, Stupid, Love.”