During the Vietnam War, decorated soldier Vince Deacon discovers Slater has become a traitor and joined the Viet Cong. Deacon beats and captures Slater, who vows revenge.
Years later, Deacon is married, has a son, and is a Los Angeles Police Department SWAT captain with a reputation for violence in the line of duty. Slater, who has become a crime boss, discovers Deacon's whereabouts and sends thugs to his home. Deacon kills one of them while protecting his family, leading to his suspension.
Deacon and his family take a vacation to camp near a lake, but Slater tracks them down and orchestrates a bombing that kills Deacon's wife and son.
Driven by vengeance, Deacon tracks Slater to Pinesville, a small California mountain town. During his investigation he discovers the local sheriff is Slater's brother and allows his criminal activities. Undeterred, Deacon continues his pursuit, battling against resistance from the deputies and local townspeople.
As his campaign goes on, Deacon slips into shell shock and begins believing he is still in Vietnam. He gathers weapons and leaves them in the woods near the town before stealing a high-power rifle from a local gun shop and going to war with Slater's gang. Their battle overruns the town, and Deacon finally manages to kill Slater.
However, Slater's death prompts his brother to pursue his own vendetta against Deacon, and he calls in the National Guard.
Deacon retreats into the woods outside the town, pursued by the deputies and the Guardsmen. His former superior officer, Colonel Cain, also arrives, hoping to end the conflict diplomatically. Cain goes in to speak with him. At first, Deacon is unable to see sense and even points his gun at Cain, but Cain manages to get through to him and calm him down. Deacon begins descending the mountain with Cain, only for Cain to suddenly be shot dead. With his spirit and grasp on reality both completely shattered, Deacon unleashes a hail of bullets on the men encircling him. He is injured when they return fire, but defiantly keeps shooting as the overwhelming forces advance upon him.
