Xia, a young girl who has dreamed of diving since childhood, neglected to check her breathing regulator during a dive, causing her best friend Gong Xu to never wake up after the dive. Xia, who had been feeling guilty and blaming herself, became ill from then on. On the first anniversary of Gong Xu's death, Gong Xu's friend from abroad, Muzi Nan, came back to pay his respects and met Xia by chance. Tell her, if you are afraid of the deep sea, then go to the forest with me!The story has silent gua...