From Parks and Recreation star Chris Pratt's incredible jump to Hollywood's A-list with the massive success of Guardians of the Galaxy, to Ariana Grande's transition from Nickelodeon child star to one of music's biggest divas, check out the stars who made major moves in 2014.
Channing Tatum, Oscar-worthy performer:
While Channing Tatum has continued to impress his critics with smart career choices following his Step Up beginnings, it wasn't until this year's Foxcatcher that critics began to take serious note of his acting abilities.
Critics initially signaled out an unrecognizable Steve Carell's performance in the psychological sports drama -- about an Olympic wrestler (Tatum) and his disturbed multi-millionaire sponsor (Carell) -- but Channing's intense performance has steadily been generating plenty of Oscar buzz.
"Carell is good in a brooding, atmospheric movie but Channing Tatum and Mark Ruffalo are better," The Daily Beast writes in a review of the film. " ... With a mouthpiece to elongate his lower jaw, Tatum is perfect as a beefed up ‘80s athlete in double denim. The battle to reach his athletic potential while his head was screwed up by doubts, insecurities, and the influence of du Pont was brilliantly realized."
At the film's premiere in November, Channing admitted to ET that filming the dark drama definitely took its toll on him.
"It was kind of depressing," he shared. "It was cold, we were away from our families, it was tough. These were dark people in a dark story to portray."
But it may all be worth it if Channing gets an Oscar nomination, despite getting snubbed at the Golden Globes this year.
Reese Witherspoon, powerhouse producer:
Reese Witherspoon was on a mission to tear down her one-dimensional America's Sweetheart image this year by taking on her most challenging role to date, playing a heroin addict in Wild. This year she also proved she's much more than an actress by becoming a powerhouse producer with film adaptations of both Wild and Gone Girl.
"It wasn't as if there was a lack of roles being offered to me," Reese told Glamour magazine recently about fighting for the role of the real-life Chery Strayed in Wild. "It was the dynamic aspect of playing a really interesting, complicated person that was not readily available. Honestly, I don’t know a woman who isn't complicated. It's strange that you don't see many complicated women on film; complicated meaning complex, I should say.'"
"I certainly didn't self-identify as anyone's sweetheart," she added about getting people to see her outside of her good girl on-screen persona. "I'm friendly, but I don't think I'm sweet. I'm honest."
Jake Gyllenhaal, method actor:
When it comes to physical transformations, nobody did it better than Jake Gyllenhaal this year. The Nightcrawler star shed 30 pounds off his already lean frame to transform into Lou Bloom, a determined reporter who chases shocking crime stories around Los Angeles.
"I could feel that he needed to be hungry, you know, and I wanted to explore that idea," Jake told ET in October about his motivation.
He later shocked fans again earlier this month, looking completely unrecognizable in the first image from his new film Southpaw. Gyllenhaal beefed up in a big way to play Billy Hope, a boxer who fights his way to the top of his sport.
Like Christian Bale before him, Gyllenhaal has taken the physical transformation as seriously as the emotional one in order to deliver powerful performances on screen.
Kendall Jenner, fashion's muse:
This year, Kendall Jenner went from a minor player in E!'s Keeping Up with the Kardashians to a supermodel. Landing features in Vogue and walking the runway for seemingly every high-fashion brand including Marc Jacobs and Chanel, she also became the youngest face of Estee Lauder ever at just 19 years old.
According to Kendall, her famous family had nothing to do with her rapid rise in the fashion world.
"In reality, I worked pretty hard for this, like running around doing tests," Kendall told ABC News in November. "It wasn't just like I got it magically [snaps fingers] and it just happened."
Ariana Grande, the new chanteuse:
Initially only recognizable from her roles on Victorious and Sam & Cat, Ariana Grande became a music superstar in 2014 with such hits as "Problem," "Right There," and "Love Me Harder." Thanks to her well-received sophomore album My Everything, Grande shed her Nickelodeon past and was dubbed the next Mariah.
But alongside the fame came the reports of her alleged "diva" reputation.
Though according to Ariana, nothing could be further from the truth.
"If any of the things that they were saying were true, I wouldn't mind it," Ariana told ET special correspondent Elvis Duran at the iHeartRadio Music Festival in September. "Since they're not, I just sort of have to focus and stay on track and do what my family has always told me, which is just: 'Know my truth, work hard, be nice to everyone you meet, not fight back and just be a lady.'"
Chris Pratt, leading man:
To say Chris Pratt had a game-changing year is an understatement. Thanks to the commercial and critical success of Guardians of the Galaxy, Chris became a full-blown superstar whose charming interviews had people calling him the male Jennifer Lawrence.
And his transformation has also been a physical one -- he lost an incredible 60 pounds in six months for the coveted Marvel role.
"I actually lost weight by eating more food, but eating the right food, eating healthy foods and so when I was done with the movie my body hadn't been in starvation mode," he told People in August. "It wasn't like I was triggered to just gorge myself and get really fat again."
With a super-successful 2014, Chris's star is only set to go higher with a major role in the feverishly anticipated Jurassic World, out June 12.
Check out one of Chris' most endearing interviews ever -- which included him French-braiding an ET intern's hair -- in the video below.