Chris Hemsworth is the latest celeb to show off his extremely different body — and overall appearance. Looks like Hemsworth is starring in the film In the Heart of the Sea, which is why this hunk took his workout regimen to the next level. He looks extremely slender and has definitely kept up with #NoShaveNovember. He shocked the hearts of mega fans around the world when he posted his photo on Twitter and Instagram, but he made sure to let us know that it's not something he'd suggest people run out and do.

"Just tried a new diet/training program called "Lost At Sea". Wouldn't recommend it..#IntheHeartoftheSea"

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Celebrities are known to go on rigorous diets and endure hardcore training programs in order to fully immerse themselves in the roles that they've taken on. While some may gain weight, others are tasked with losing it — both truly showcasing their dedication to their craft. In addition to this Hemsworth brother's incredible change, we rounded up eight other iconic actors who took it to the next level for their roles. 

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1

Matthew McConaughey

Matthew McConaughey went through a major transformation for the film Dallas Buyers Club. He lost a whopping 47 pounds to stay true to his role of Ron Woodroof and even kept a diary of how he did it

2

Natalie Portman

Black Swan starlet Natalie Portman shed 20 pounds to depict a professional ballerina. She also underwent a strength training and ballet regimen an entire year prior to filming — talk about commitment! 

3

Jake Gyllenhaal

Not only did Jake Gyllenhaal gain 28 pounds for the movie Southpaw, but he also picked up a new sport: boxing. 

4

Charlize Theron

Instead of losing weight, Charlize Theron was tasked to gain it in her epic role for the movie Monster. She put on 30 pounds to identify with her character, Aileen Wuornos

5

Anne Hathaway

Anne Hathaway went down 20 pounds for her role as Cosette in the iconic Les Misérables film. The actress said she didn't eat for 13 days straight, but does not advise people to follow suit if they're trying to lose weight. 

6

Christian Bale

Christian Bale made people's jaws drop with his serious change for The Machinist. He looked almost unrecognizable as he became 64 pounds lighter in a mere four months. 

7

Renée Zellweger

Renée Zellweger won hearts with her role in the Bridget Jones's Diary movies. She gained 30 pounds for the first film, as well as the sequel. 

8

Tom Hanks

Tom Hanks is known for his transformative roles and lost weight for the beloved movie Cast Away. But because the actor has diabetes, it's probably not the wisest way for him to literally give it all he's got.