Chris Hemsworth is usually fairly reliable eye candy, but he's not looking quite so handsome in this latest movie trailer!

The Australian actor stars alongside Cillian Murphy in Ron Howard's film In The Heart of the Sea which comes out at the end of this year – and fans will be shocked to see the dramatic image transformation he undertook for the role.

Look at that grizzled face… is our favourite clean-cut actor under there somewhere?!

Chris plays a sailor who is forced to take gruesome measures to survive at sea with his crew after their ship is attacked by a sperm whale. Basically… if you're thinking cannibalism, you'd be correct. Shudder.

The actor went on a crash diet to lose weight for the later stages of the movie, eating just 500 – 600 calories a day to look thin enough for the role. As a regular gym buff, Chris said it was difficult to see his fat and muscle dropping away.

"It's funny, you've never heard 15 big, burly guys playing sailors talk about their calorie count, what they should and shouldn't eat, what their cheat meal is going to be," he told Jimmy Kimmel last year.

And if you thought that 600 calories seemed like a lot – it's definitely not. "I mean, you can consume 600 calories in a milkshake. So it ends up being a couple of small salads, a couple of small pieces of protein and that's kind of it and you go to bed hungry," he admitted. "Then you have like a fasting period of 15 hours, like you stop eating completely, and then you have little meals through the day."

Poor Chris – we hope the new film was worth it!