Brad Pitt has called his new survival thriller "Heart of the Beast" the most physically demanding film of his career. The film follows a former Special Forces soldier and his military-trained dog as they fight for survival in the Alaskan wilderness, and reunites Pitt with director David Ayer, who previously worked with him on "Fury".

Filming proved gruelling due to the extreme conditions required for authenticity; Pitt revealed that actors would become soaked first thing in the morning and remain wet throughout the entire day. Despite these demanding physical circumstances, Pitt said he was primarily drawn to the project by its emotional ending, which moved him to tears when he first read the script. The film features a real search-and-rescue dog as Pitt's scene partner and explores themes of PTSD and trauma experienced by veterans.