In 1908, Korean independence fighters led by Ahn Jung-geun (Hyun Bin), achieve a significant victory in a battle against the Japanese army in Sina Mountain, near the northern border of Korea. Lieutenant General Ahn Jung-geun of the Korean Independence Army, upholding the principles of laws of war, releases Japanese war prisoners. However, this action gives rise to suspicions about him, causing fractures within the ranks of the independence fighters.

A year later, a group of like-minded activists - Ahn Jung-geun, Woo Duk-soon (Park JeongMin), Kim Sang-hyun (Jo WooJin), Ms. Gong (Jeon YeoBeen), Choi Jae-hyung (Yoo CheaMyung) and Lee Chang-sup (Lee DongWook) - determined to reclaim their homeland, gathers in Vladivostok. Upon learning that Ito Hirobumi, the Japanese statesman and the first Japanese resident-general of the occupied Korea, is heading to Manchuria for negotiations with Russia, Ahn and his men set their course for Harbin. The Japanese army, armed with intelligence on the resistance operation, promptly initiates pursuit...