The young man Tian Shui (played by Jin Kang Yu), who is well-versed in swimming, has lost his savings in gambling and has fallen to the point of teaching swimming and cleaning in a swimming hall. He is confronted and beaten up by a group of thugs, but fortunately, another group appears just in time to save his life. After testing his swimming skills, they take him into a small room, where Tian Shui meets drug lord President Jiang (played by Zhao Zai Huan). He is told that if he helps them with a small task, his debt on high-interest loans will be wiped clean. It turns out that this drug trafficking organization is planning an international drug trade and is looking for a 'sea boy' to help transport their latest drugs across the ocean to Japan, making Tian Shui their newest target. At the same time, he is also under the watch of police officer Jin (played by Lee Won Yu), who arrests Tian Shui under the pretext of his gambling involvement and demands that he go undercover within the drug trafficking organization. During his interactions with President Jiang, Tian Shui unexpectedly meets Jiang's daughter, Yu Li (played by Park Shi Yeon). From this point on, Tian Shui's life descends into a peculiar journey filled with crises.