Brad Pitt opens up about 'miserable' experience shooting gripping survival thriller Heart of the Beast

Surviving a wolf pack attack, a plane crash, ‘hypothermic’ conditions and a whole lot more, Brad Pitt’s latest film is quite the ride.

Heart of the Beast follows former US special forces soldier James Belmont (Pitt) trapped in the Alaskan wilderness with his trusty combat dog, Odin.

The pair pretty much defy death through the course of the film (which is currently sitting at a mega 91 percent on Rotten Tomatoes) all overshadowed by their PTSD.

So yeah, as you can imagine it’s a lot. And it sounds like it was a lot to go through, as Pitt tells LADbible that at some times it ‘was miserable’.

While his character suffers, struggles and pushes through, he changes before our eyes.

Noting it was ‘not easy’, Pitt largely credits costume and makeup to portray this transformation, but director David Ayer also points out the attention to detail the star put in.

Belmont and Odin are forced to fend for themselves in the wilderness, facing threats of drowning, bear attacks, hypothermia, lack of food and, well, bleeding to death.

Obviously, this all takes quite the physical toll on the former soldier as Pitt explains: “Costume and makeup were incredible, just to calibrate the degree of decline through wardrobe, through injury was pretty exceptional.

“It was really an integral part of telling the story.”

Ayer adds: “Just the way the wardrobe changes over time or how the injuries affect Brad’s physical performance or just how he deteriorates was something he had to track very carefully in his performance.

“There’s so much thought and detail that went into that. It was an entire layer beyond everything else.”

Emphasising this point and the absolute physical toll the film took on Pitt in general, the director continues: “He’d be limping in a shot, I’d call ‘cut’ and then he limps off set even more.

“So he had to calibrate his limping for the time in the story.”

The film follows Belmont and Odin on quite the journey. (Paramount Pictures)

Ayer praises Pitt for his ‘amazing’ dedication to the film, as he’d stay on set ‘cold and wet and exhausted’ as they prepared the shots.

And it sounds like those are exactly the right adjectives as the actor says it was ‘freezing’ to film.

While Heart of the Beast may be set in Alaska, the crew shot in New Zealand, using the incredible scenery ‘in the middle of nowhere’ amid the rough weather and the ‘little of human comforts’.

“It was hypothermic, it was miserable,” Pitt explains. “It’s not fun but I signed up for it – I love a survival movie. We mostly knew what we were in for, not to the degree, but most of the crew was in the water suffering with me.

“And we’d start the day wet and we’d end the day wet.”

Pitt says the crew dealt with 'freezing' conditions. (Paramount Pictures)

Stunt performer Joel Abadal did some ‘heavy lifting’ for Pitt, but he did indeed get into the water, trapped in the upside down plane.

“I didn’t know he could hold his breath that long – thank God he could,” Ayer joked.

As Pitt added: “I didn’t either by the way, I didn’t either.”

But as the transformation of not just his appearance but his physicality plays out throughout the film, the star credits the ‘exceptional’ shots directed by Ayer as trust me, viewers are set to be left in tears.

Heart of the Beast is in cinemas across the UK now and in the US from 25 September.