In June 2005, a four-man SEAL team is tasked with a covert mission, codenamed Operation Red Wings, aimed at locating and eliminating a high-ranking Taliban leader named Ahmad Shah in the mountainous region of Afghanistan. The team, led by Lieutenant Michael Murphy, includes sniper Marcus Luttrell, gunner’s mate Danny Dietz, and sonar technician Matthew 'Axe' Axelson. After being inserted into the Hindu Kush mountains, the SEALs establish an observation post to keep watch on a village where Shah is believed to be hiding.

As the mission progresses, the team's position is compromised when they inadvertently encounter local goat herders. The SEALs face a difficult moral decision: release the herders and risk the operation being disclosed, or eliminate the potential threat in order to ensure the mission's success and their own safety. Choosing to adhere to the rules of engagement, the team sets the herders free. Shortly afterwards, the SEALs find themselves surrounded and outnumbered by Shah's forces. A fierce and relentless battle ensues as they struggle to survive against overwhelming odds, calling on their training, brotherhood, and sheer determination.