Finally enlisted as a Marine, Eugene Sledge trains for combat at Camp Elliott; and the 1st Marine Division land at Cape Gloucester on the Japanese-held island of New Britain.
After the Japanese surrender, Leckie leaves the hospital and returns home; Sledge heads back to Alabama to be reunited with his family and Sid Phillips; and Lena visits Basilone's home.
Basilone's celebrity grows while on the war bonds tour; and Sledge gets his first taste of combat as he, Leckie, and the 1st Marine Division meet fierce Japanese resistance on the island of Peleliu.
After battling across Okinawa, Sledge and the rest of the 1st Marine Division are ordered to relieve an Army division that has been in combat against the most strongly defended position on the island.
Despite the suffocating 115-degree heat and a lack of clean drinking water, Sledge, Leckie and the other Marines confront the highly-fortified enemy as they attempt to capture the Peleliu airfield.
Basilone and the 7th Marines arrive on Guadalcanal to reinforce Leckie and the rest of the 1st Marine Division as they continue to defend the crucial airstrip.
Physically and mentally debilitated after the four-month ordeal on Guadalcanal, Leckie, Basilone and thousands of their comrades land in Melbourne, where they're greeted by adoring crowds.
In the immediate aftermath of the Japanese attack on Pearl Harbour, Marine Sergeant John Basilone and his troops prepare to ship out and confront the enemy somewhere in the Pacific.