Chris Taylor, portrayed by Charlie Sheen, is a young American who opts for a life in the infantry, departing from his privileged university background to volunteer for combat in Vietnam during September 1967. Upon arriving in Da Nang, South Vietnam, he is confronted with the grim reality of war as he observes dead soldiers being loaded into body bags on his plane. Assigned to Bravo Company of the 25th Infantry Division, stationed "somewhere near the Cambodian border," Taylor's initial enthusiasm quickly diminished amidst the grueling work and harsh living conditions.
One evening, Taylor's platoon commander, Lieutenant Wolfe (played by Mark Moses), discusses the upcoming patrol plans with his sergeants: the sympathetic Sergeant Elias (played by Willem Dafoe), the brutal Staff Sergeant Barnes (played by Tom Berenger), the cowardly lifer Sergeant Red O'Neil (played by John C. McGinley), and the troubled Sergeant Warren (portrayed by Tony Todd). A tension-filled argument erupts between Barnes and Elias about sending new recruits on a potentially deadly patrol, culminating in O'Neil insisting they go instead of the more seasoned soldiers. Eventually, an agreement is struck, which sees O'Neil ordered to join the new troops.
That night, North Vietnamese soldiers attack Taylor's unit as they sleep. Tragically, fellow recruit Gardner (played by Bob Orwig) is killed, and another soldier, Tex (portrayed by David Neidorf), is severely injured. Taylor, although not directly culpable for the incident — O'Neil's action of throwing a grenade leads to Tex's injury — finds himself blamed for the casualties. Suffering only a light injury to his neck, he is sent to a field hospital for recuperation.
After returning from the hospital, Taylor connects with the "heads," a close-knit group led by Elias who indulge in socializing, dancing, and drug use in a hidden bunker. During a patrol on January 1, 1968, tragedy strikes as two platoon members, Sandy (played by J. Adam Glover) and Sal (portrayed by Richard Edson), die when they accidentally trigger a booby trap. Shortly thereafter, they discover the gruesomely mutilated body of Manny Washington (portrayed by Corkey Ford), heightening the tension within the platoon.
As the troops venture into a nearby village, they uncover a stash of food and weapons, but the situation escalates dramatically when Bunny (portrayed by Kevin Dillon) brutally murders a mentally disabled boy despite O'Neil's orders to leave. In a fit of rage, Barnes kills the village chief's wife and nearly slaughters his daughter, but Elias intervenes, resulting in a fierce altercation between the two sergeants. With the passive Lieutenant Wolfe failing to take a stand, orders eventually come down from a higher authority to raze the village to the ground.
Tensions rise as the platoon splits, with some siding with Elias and others aligning with Barnes. In the chaos that follows, a patrol is ambushed, and heavy casualties ensue, including the grievous injury of Big Harold (played by Forest Whitaker). Mired in confusion, Barnes takes command after Wolfe's miscalculation in artillery support leads to the death of many his own men. He subsequently abandons Elias, leaving him severely wounded during the ensuing chaos.
In a moment of reckoning, Taylor finds himself faced with a severely injured Barnes, who, in his arrogance, believes there’s no threat. But when Taylor’s finger is pressed against the trigger, the dynamic shifts dramatically. Ultimately, in a desperate act of survival, Taylor pulls the trigger, killing Barnes and grappling with his own morality.
The war proves to be nothing short of hellish, and in the aftermath, Taylor bears witness as the remnants of the platoon are rescued. As he boards the helicopter, he reflects on the legacy of war, forever haunted by the specters of Barnes and Elias, as he comes to terms with the new version of himself that will emerge from the ashes of conflict, forever marked by the brutality of Vietnam.
