Cheung Chau Island in Hong Kong is a small place where people are born and raised. They can enjoy a comfortable life without too much ambition. However, there is a stubborn "Cheung Chau Beauty" Luo Jiao (played by Gillian Chung). In order to avenge the slap of her rival, she is determined to drag a few good sisters to participate in the "Water Lily" 4x100 swimming relay to win the championship. To this end, she kidnapped the "Flying Fish Prince" Guo Zhiyuan (played by Alex Fong) and forced him to train herself and her sisters: the sickly girl Ayu (played by Huang Shengyi) who was destined to be alone, and the herbivorous twins "Dahua" (played by Xi Limei) and "Xiaohua" (played by Zhu Xun). After some hard training, and with the superpowers given to her by the "Sea Goddess of Mercy" (played by Tian Liang), Gillian and her sisters' swimming skills soared, and Guo Zhiyuan gradually fell in love with Gillian, but she misunderstood that he liked Ayu. The competition finally arrived, and the "Sea Goddess of Mercy" appeared and helped Gillian and her team win. However, the love between Gillian and Guo Zhiyuan also came to an end when Zhiyuan was picked up by his agent...