Hard nosed North Korean naval officer Choi Baek-du (Jeong Jun Ho) and his light-hearted sergeant Lim Dong-hun (Kong Hyeong Jin) go on a fishing trip in the Sea of Japan. The pair fall asleep in their boat and are violently awoken by a squall. Clinging to their tiny craft, they struggle to survive the storm. By the time the storm passes, they have been washed deep into South Korean borders. Realizing their plight, they conceal their boat and explore their surroundings.
They are continually shocked by the culture of South Korea, but eventually recover their bearings and befriend a girl, Han Nara (Ryu Hyeon-kyeong). Unfortunately for the sailors trapped in enemy territory, Nara is a runaway and her father is a police chief, which only makes it more difficult for them to blend in. After their repeated attempts to escape fail, they enter a talent contest in order to with the first place prize: a trip to Kumgang Mountain, North Korea.