In the summer of 1980, a North Korean soldier crosses the Demilitarized Zone at the risk of his life. Coming to find his father, he is shot by North Korean forces, loses his memory, and is captured by the South Korean military. Subsequently, the South attempts to find the young man's father. Three individuals are selected from numerous candidates whose hometowns are in the North, after undergoing genetic screening. These three men strive to revive the young man's memory, thinking he might be their son, but without much success, they become disappointed and turn away. However, one of them, Han Woo-hyun, insists on attempting to restore the young man's memory through brain surgery, which ultimately costs the young man his life. Shocked, Woo-hyun loses his reason and silently walks into the military demarcation line, driven by longing for his son and wife left behind in the North. Unfazed by the gunfire and commotion from both sides, he walks alone, carrying the people he misses in his heart. (Lim Jae-won)