Yes, this is Chris Hemsworth

He's known for muscle-bound roles in The Avengers and Thor, but Chris Hemsworth has undergone a dramatic makeover for his new role.

Hemsworth dropped 15kg for his part in the Ron Howard movie In the Heart of the Sea, the Moby Dick-inspired film due for release next week.

The Australian actor posted a dramatic photo of his weight loss on Instagram recently, and told Kiss FM in Australian he received advice from Cast Away Star Tom Hanks on how to lose the weight.

"We called up Tom Hanks and he gave us some advice on how to lose the weight ... don't eat. Pretty straight-forward."

View this post on Instagram

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

A post shared by Chris Hemsworth (@chrishemsworth) on Nov 22, 2015 at 1:56pm PST

He kept the diet up during filming and admitted it helped him with the role.

Hemsworth plays Owen Chase, a sailor stuck at sea for 90 days while his boat is chased by a killer whale.

"We felt as if we were going to pass out any second. Looking back, it was essential to doing the story justice ... There wasn't a lot of acting required for those last couple of weeks."

In the Heart of the Sea is due for release in New Zealand cinemas next week.

- nzherald.co.nz