Wan Zhi (Xue Jingqiu), a native of Haeundae, Busan, South Korea, lives in a quiet place. He has lived on a fishing boat since he was a child and has been working with his most dependent father, Yan Xi. Unexpectedly, in 2004, the most shocking Indonesian tsunami happened. At that time, two people on a fishing boat in the Indian Ocean died because of Wan Zhi's misjudgment, which made Wan Zhi, who had always secretly loved Yan Xi (Ha Ji Won), afraid to confess because of his guilt. Finally, one day, Wan Zhi got up the courage, decided to show his love to Yan Xi, and prepared a romantic proposal. However, Wu Dongchun (Jin Renquan), a middle school classmate in Yan Xi, is not optimistic about this evil couple. Wan Zhi's younger brother Zhi Heng (Li Minji) is a lifeguard at sea. In an action, he met a rich girl, Kim (Jiang Yiyuan). In their communication, they have many misunderstandings.

On the other hand, Virgin Yan Zhenghua promoted Haeundae as the image ambassador of the World Expo. She has a daughter with her ex-husband Hui Jin (Park Joong-hoon), who is a geologist at the International Institute of Oceanography, but now she has found another lover. Hui Jin found that the geological conditions around Malaysia and Haeundae in the East China Sea were very consistent with the Indonesian tsunami in 2004. Dr. Kim, who was uneasy, repeatedly suggested that the tsunami might happen in South Korea, but the disaster prevention department ignored his suggestions and judgments, stressing that a similar tsunami could not happen in South Korea, and Dr. Kim could only bear the hidden worries himself. Unexpectedly, the shape of the East China Sea began to change unpredictably, and Dr. King's prediction came true, but it was too late to defend at this moment. Millions of people who come to Yuntai for vacation in summer and live a quiet life don't know that a terrible disaster is coming, which will destroy the whole Yuntai. Lovers and Dr. Jin, his wife and daughter (Jin Yourong) just confirmed each other's wishes, and their happiness was washed away by this ruthless tsunami.