Duffy, a drifter and veteran haunted by the trauma of combat and the deaths of comrades he considered brothers, struggles to settle down. His time in active service caused such upheaval in his life that he wanders from place to place with only a suitcase, driven by the need to make just enough money to reach his next stop. Currently, he finds himself in Los Angeles. One night, he gets into a fight at a roadhouse bar when someone tries to cheat him at poker, and he easily beats up a group of bullies.
Max, an ex-con and manager of fighters for an underground fight club, witnesses the brawl and sees in Duffy a lot of skill, potential, anger, and a desperate need to prove himself. Max is reminded of his brother, a fellow veteran who committed suicide because he didn’t have an outlet for his rage and isolation. Fearing that Duffy could end up the same way, Max offers him a chance to win some money for both of them, as well as a temporary home with himself, his sister Rachel, and her daughter.
Max is in dire need of money to repay Sage, one of the villains who runs a gym and the underground fights. Sage’s boss, Ellen Ridgeway, is a police detective who uses her official status to intimidate and control the entire criminal operation. With Max’s guidance, Duffy wins the fight and the money. However, he becomes unintentionally entangled in a complicated web because the money had originally been stolen from Sage and Ridgeway by Rachel’s abusive boyfriend.
Rachel’s boyfriend had hidden the theft from everyone, making Duffy’s victory in the underground fight unknowingly place him at the center of Sage and Ridgeway’s attention. Ridgeway, using her influence as a detective, begins to tighten her grip on the situation, applying pressure on Max and his makeshift family. Duffy’s involvement with the underground fight club not only rekindles his combat instincts but also brings back haunting memories of his time in the service.
As Duffy integrates into Max’s household, he forms a bond with Rachel and her daughter, feeling a sense of belonging he hasn’t experienced since his military days. Despite his growing attachment to them, the constant threat from Ridgeway and Sage looms over him, threatening to dismantle the fragile stability he has found. Max, too, is torn between protecting his sister and her daughter and using Duffy’s fighting skills to finally clear his debts and break free from Ridgeway’s control.
In a final confrontation, Duffy decides to take a stand, not just for himself, but for the new family he has come to care for. He prepares for one last underground fight, aware that this could either secure their freedom or plunge them deeper into danger. The fight becomes a test of his resolve, pitting his combat-honed instincts against the ruthless underworld controlled by Ridgeway and Sage.
Through sheer determination and the support of Max and Rachel, Duffy emerges victorious. He manages to break free from the oppressive grip of the underground fight club and Ridgeway’s criminal network. Although the future remains uncertain, Duffy finds a renewed sense of purpose and hope, realizing that he can finally start to rebuild his life with the family he has chosen.