August 18, 1966. Late Afternoon. South Vietnam.

For three and a half hours, in the pouring rain, amid the mud and shattered trees of a rubber plantation called Long Tan, Major Harry Smith (Travis Fimmel) and his dispersed company of 108 young and mostly inexperienced Australian and New Zealand soldiers are fighting for their lives.

They are holding off an overwhelming enemy force of 2,000 battle-hardened Viet Cong and North Vietnamese soldiers. With their ammunition running out, their casualties mounting and the enemy massing for a final assault, each man begins to search for the strength to triumph over an uncertain future with honour, decency and courage.