In the Joseon Dynasty, two friends who grew up together — one the master and one the servant — reunite post-war as enemies on opposing sides.

Pil-ju, an Alzheimer's patient in his 80s, who lost all his family during the Japanese colonial era, and devotes his lifelong revenge before his memories disappear, and a young man in his 20s who helps him.

An education officer who was dispatched died after a gunshot went off in the dead of night. At the same time, deserters flee to the DMZ in the access control zone, and the 3rd platoon is urgently deployed to the DMZ search operation. There, the crew sees an unidentified soldier, not a deserter or a search crew.