The protagonist Wu Liuqi originally lived a carefree life on Xiaoji Island, but his identity became a mystery due to amnesia. As outsiders landed on the island and recognized Wu Liuqi, various conspiracies began to cover Xiaoji Island. So Wu Liuqi decided to return to Xuanwu Kingdom to meet his destiny in order to protect his partners and their homeland.
(Source: Bilibili, Google translated)