Paul Kersey is a Chicago-based trauma surgeon whose life is turned upside down when his wife and daughter are brutally attacked in their suburban home during a burglary gone awry. With his wife killed and his daughter critically injured, Paul finds himself engulfed in grief and anger. The police are overwhelmed with cases, leaving Paul's family's ordeal unsolved and pushing him towards a profound sense of helplessness and frustration. Living in a city plagued by violence, Paul starts to see the grim reality that the system is failing to protect innocent citizens.

Driven by a desire for justice and a sense of powerlessness within the legal system, Paul embarks on a vigilante quest to seek vengeance against the perpetrators. His transformation from a caring surgeon to a man on a mission for retribution introduces him to the city's darker underbelly. As he delves deeper into this world, he uses his medical knowledge to exact revenge, turning the tables on criminals who have long evaded the law. This path sets him on a dangerous and moralistically dubious journey, forcing him to navigate the complexities of justice, vigilantism, and the consequences of taking the law into his own hands.