The book begins with John Rambo, a Vietnam war veteran, hitch hiking in Madison, Kentucky. He is picked up by Sheriff Teasle and dropped off at the city limits. When Rambo repeatedly returns, Teasle finally arrests him and drives him to the station. He is charged with vagrancy and resisting arrest and is sentenced to 35 days in jail. Being trapped inside the cold, wet, small cells gives Rambo a flashback of his days as a prisoner of war in a Viet Cong prison camp, and he fights off the cops as they attempt to cut his hair and shave him without shaving cream, beating one man and slashing another with the straight razor. He flees, steals a motorcycle, and hides in the nearby mountains. He becomes the focus of a manhunt that results in the deaths of many police officers, civilians, and National Guardsmen.
In a climactic ending in the town where his conflict with Teasle began, Rambo is finally hunted down by special forces Colonel Sam Trautman and Teasle. Teasle, using his local knowledge, manages to surprise Rambo and shoots him in the chest, but is himself wounded in the stomach by a return shot. He then tries to pursue Rambo as he makes a final attempt to escape back out of the town. Both men are essentially dying by this point, but are driven by pride and a desire to justify their actions. Rambo, having found a spot he feels comfortable in, prepares to commit suicide by detonating a stick of dynamite against his body; however, he then sees Teasle following his trail and decides that it would be more honourable to continue fighting and be killed by Teasle's return fire.
Rambo fires at Teasle and, to his surprise and disappointment, hits him. For a moment he reflects on how he had missed his chance of a decent death, because he is now too weak to light the dynamite, but then suddenly feels the explosion he had expected—but in the head, not the stomach where the dynamite was placed. Rambo dies satisfied that he has come to a fitting end. Trautman returns to the dying Teasle and tells him that he has killed Rambo with his shotgun. Teasle relaxes, experiences a moment of affection for Rambo, then dies.
Reviews for the book lambasted it for its excessive violence, although the suspense was praised. Shortly after its publication, the rights were sold to Columbia pictures, then Warner Bros until it was sold to Andrew G. Vajna and Mario Kassar, who turned the character of Rambo into a more likable underdog who never killed anybody, instead of the angry, psychotic character in the book who goes on a bloody rampage. The role was offered to many celebrities like Dustin Hoffman and Al Pacino until it reached Sylvester Stallone. The film was well-recieved by critics and saved Stallone's career.