In a major scene at the end of "Platoon", the command bunker is destroyed by a North Vietnamese Army (NVA) suicide bomber. The desperate company commander, Captain Harris (Dale Dye), orders U.S. Air Force pilots to "expend all remaining ordnance" inside his perimeter. During the chaos, Sergeant Bob Barnes (Tom Berenger) and Private Chris Taylor (Charlie Sheen) come face-to-face. As Barnes is about to kill Taylor with a shovel, the two are knocked unconscious by the last-ditch American napalm attack.

A wounded Taylor regains consciousness the next morning. He has a serious wound to his lower abdomen. He soon finds Barnes, who is also wounded after being shot in both legs. Taylor takes an AK-47 rifle from a dead enemy soldier and aims it at Barnes. Barnes at first doesn't feel threatened, and he dismissively orders Taylor to call a medic. When Taylor does not comply, but instead continues to aim his weapon, Barnes (tired of the fighting) tells him to pull the trigger by saying: "Do it!" Taylor shoots Barnes three times in the chest, killing him. Taylor then drops his rifle. He will collapse on sandbags; he is next given medical attention.

Interestingly, although not in the script, Taylor is seen on the verge of pulling the pin of a grenade that he found, only to drop it as reinforcements come to Taylor. (Sheen thought that Taylor would be suicidal after killing Barnes. Director Oliver Stone thought that the impromptu act was so good he decided to keep it in the film.)

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