In every city, 9 out of 100 people are mentally troubled. Psychiatrist Gao Jing (Angelica Lee) puts the health of her patients first in her work and is loved by her colleagues. She passed by a man in a bookstore, and the man bought the photography book she wanted to buy. Gao Jing felt a little strange. Xiao Kai (Isabella Leong) is Gao Jing's patient. After returning from vacation, he took Gao Jing to a photography exhibition. Gao Jing accidentally discovered that the person in the photo was diving herself. What's more unexpected is that the photographer was the man she met in the bookstore that day, and also Xiao Kai's brother - archaeologist Chen Guodong (Guo Xiaodong). Guodong gave Gao Jing the book he bought that day, and the two fell in love. In order to propose to Gao Jing, Guodong, Gao Jing and Xiao Kai went to Yonaguni Island and dived deep into the sea to find the diamond ring hidden there. Who knew that Guodong had an accident and only salvaged a headless male corpse. Gao Jing lost her memory of the accident due to excessive grief. Xiao Kai was unusually cold towards her. Gao Jing sought hypnosis from the dean (Tony Leung), but she had more hallucinations after hypnosis.