Marine Robert Leckie has his first taste of combat on Guadalcanal, while privileged Eugene Sledge longs to join the war.
As the fighting intensifies, Marine John Basilone prepares to hold off a massive assault by Japanese forces.
The Marines head to Australia for some much-needed R&R. As Leckie falls for a local girl, Basilone receives some sobering news.
When a missing MI6 Officer is linked to a murdered petty officer, Gibbs sends Quinn and Bishop to Philadelphia to work with MI6 Officer Clayton Reeves.
A World World I pilot exposes Roxton's wartime record leading to some important revelations regarding the explorers connections.