CHRIS Hemsworth is known for bulking up to play his most famous movie character, the hammer-wielding and muscular Norse god, Thor.
But the Aussie heartthrob went through a completely different transformation for his latest role in director Ron Howard's In the Heart of the Sea.
Hemsworth plays Owen Chase, first mate of the whaling ship the Essex, who was left stranded at sea off the Pacific coast of South America after the Essex was attacked by a large, seemingly vengeful sperm whale.
The real-life 1820 tragedy inspired Herman Melville to write his literary epic Moby Dick.
The film, based on Nathaniel Philbrick's National Book Award-winning novel of the same name, depicts both the trials of the Essex crew and Melville's (Ben Whishaw) interview years later with the last survivor, Thomas Nickerson (Brendan Gleeson/Tom Holland).
"It was an exhausting shoot," Hemsworth tells Weekend.
"We went from one extreme to the other, from the freezing cold in London to boiling hot in the Canary Islands.
"We shot somewhat in sequence, so we started on a 3000-calorie diet and as the film went on the days got longer and longer and we ate less and less. The last couple of scenes we felt and looked a bit like what these men really did. I can't recommend it."
Hemsworth said he was blown away by the lengths whalers in the 1800s would go to in their hunt for whales and their precious oil, which was used to light the cities of Europe and America.
"It was insanity, like going off to war," he says.
"They would go off for two or three years. It was incredibly dangerous and brutal and hard, but that was the industry. The whale was what lit the world at that time; now we pull oil out of the ground... I was fascinated when I read the book."
The challenges faced by the survivors, who were stranded at sea for 90 days, brought new meaning to the phrase "sink or swim" for Hemsworth.
"When they're drifting on these boats all of them are forced to look inside and ask bigger questions," he says.
"And once the egos and entitlements are stripped back you see these people for who they are. In my character's case, he realised he was on a path (as a whaler) that was going to have a negative outcome.
"The survivors weren't welcomed home with a parade. They were looked at as ghosts, and once it got out about what they did and what happened - the cannibalism - that had a devastating impact. Living with that experience was pretty traumatic."
The father of three hopes cinema-goers take the film's overall message, about respecting nature and not letting greed or ego get the better of you, to heart.
"There was a big focus to make sure the whale is the hero in a lot of ways and that there is a big lesson there to not ignore history," he says.
"We like to think of ourselves as more civilised now but we do still ignore our previous mistakes."
In the Heart of the Sea opens nationally on Thursday.
In the Heart of the Sea
Stars: Chris Hemsworth, Cillian Murphy, Brendan Gleeson, Ben Whishaw, Benjamin Walker
Director: Ron Howard
Reviewer's last word: A gripping historical tale of the high seas, it's easy to see why the tragedy of the Essex and her crew inspired author Herman Melville's epic tale Moby Dick.
Star Profile: Ben Whishaw
Quirky fact: Beat out Leonardo DiCaprio and Orlando Bloom for the role of Jean-Baptiste Grenouille in Perfume: The Story of a Murderer.
Best known for: Skyfall, Spectre, Paddington, The Hour, Stoned.
If you like this movie you'll like these: Rush, The Da Vinci Code, Unbroken.
Quote: "I don't have any ambition to make lots of money or win an Oscar or anything like that. It's not about that for me. I'm very lucky to have found the thing that makes me tick."
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