On Makin Island, in August 1942, Private C. Miller witnesses the torture and execution of his squad of Marines by the Imperial Japanese Army, before he is rescued by a squad of Marine Raiders, led by Corporal Roebuck and Sergeant Sullivan, who then begin assaulting Japanese positions on the island. In September 1944, the squad participates in the Battle of Peleliu. After breaking through the Japanese lines on the beach, Sullivan is fatally stabbed by a Japanese soldier, and Roebuck is promoted to Sergeant. The squad make their way through a swamp to capture an airfield to disable anti-aircraft guns. After pushing further inland, the squad take out enemy mortar crews so their tanks can proceed inland. They proceed through the jungle to attack the artillery-filled point, allowing American ships to advance, and Peleliu falls into American hands.