The sudden death of her mother brings Myung-eun back home to Jeju island. There she meets her estranged sister Myung-ju and Myung-ju's daughter Seung-ah, still living at their old home, and Hyun-ah who has lived with them for over 20 years like a relative. A career woman whose hard exterior masks her illegitimacy and abandonment issues, Myung-eun tells Hyun-ah she wants to start looking for her father after the funeral. Single-minded in her desire to dig up memories of her father and discover why he left, Myung-eun resents that Myung-ju, who like their mother is a carefree fish trader and an unmarried mother of a young daughter, seemingly doesn't care. At first Myung-ju is reluctant to accompany Myung-eun, but after Hyun-ah persuades her, guilt and her sense of duty as an older sibling prevails. And so the two sisters who are dissimilar in character...

In August 1950, waiting for UN troops to arrive, the South Korean army assembled to protect Nakdong River. Only 71 student-soldiers are left behind to guard the city of Pohang. Now they are on a mission to defend the country from North Korean troops.