Brendan Fraser says he was forced to wear a 300lb fat suit filled with dried beans and marbles after failing to pile on "enough weight" for The Whale.
The actor, 54, needed some extra help to transform into a 600 pound obese man for the new thriller flick by director Darren Aronofsky.
Speaking of the suit, Brendan said: "There was a five-point harness that had me strapped in. Once into it, I was in there all day until it came off.
"The costume pieces themselves contained combinations of those little airsoft pellets, maybe dried beans, marbles. But the rule was that the whole look should obey the laws of physics and gravity, because we don't see that in films."
He discussed the new role, which has faced recent controversy over the use of a fat suit, in a new interview with Adam Sandler for Variety.
Brendan explained: "It's important to say this, because there are those who live with this disease.
"I felt empowered to be their voice and to be as honest as I could and as authentic as I could in the portrayal. Look, my weight has been all over the map.
"I put on weight to play this role, and it wasn't enough — so the body had to go on top of that, and the two worked together."
In the film, Fraser plays Charlie, a father who is attempting to reconnect with his daughter, played by Stranger Things star Sadie Sink.
Speaking of the controversy surrounding Brendan's casting, Darren said: "There was a chapter in the making of this film where we tried to research actors with obesity.
"Outside of not being able to find an actor who could pull off the emotions of the role, it just becomes a crazy chase. Like, if you can’t find a 600-pound actor, is a 300-pound actor or 400-pound actor enough?"
"From a health perspective, it’s prohibitive," he said. "It’s an impossible role to fill with a real person dealing with those issues," he told Variety.
The Whale is set for release on December 9 in US cinemas. A UK release date has not been confirmed or announced.
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