On her 29th birthday, Mira receives a congratulatory letter from a mysterious sender, who tells her that her biological father is still alive. Having lost her memories, Mira follows the clues left in the letter to search for him. During the process, her colleague Andy suspects she may have dissociative identity disorder and turns to Shen Bai, a psychology professor at Jiangdu University, for help treating her. As treatment progresses, Mira recovers memories of her past, only to discover that she has fallen into a massive lie. Andy's true identity draws them into a family murder case from twenty years ago. When they find traces of Mira's father in the Yandu Cemetery, they discover that the deceased there is not her father.
The baffling truth and their tangled family histories leave them at another dead end. At last, under Shen Bai's hypnosis, the two recover their complete memories. It turns out they are merely secondary personalities split off from Song Weihang. Just when Song Weihang thinks everything has been settled, her attending physician, Shen Bai, tells her they are still dreaming. It is only now that everything truly begins...