In 1942, Private Witt (Jim Caviezel) is a U.S. Army absconder living peacefully with the locals of a small South Pacific island. Discovered by his commanding officer, Sgt. Welsh (Sean Penn), Witt is forced to resume his active duty training for the Battle of Guadalcanal. As Witt and his unit land on the island, and the American troops mount an assault on entrenched Japanese positions, the story explores their various fates and attitudes towards life-or-death situations.