A sudden car accident caused Xia Qianqian to lose all her memory. When she woke up in a strange ward, she found an anonymous letter full of warnings lying on her pillow: "Don't trust anyone." What's even weirder is that the man who claims to be her fiancé has a vague calculation in his eyes, and the woman who claims to be her best friend always whispers to her back late at night.
As the memory fragments were pieced together, Qian Qian discovered that she was involved in a murder case fifteen years ago. The fire that year engulfed the entire orphanage. Now the survivors are dying mysteriously one after another, and all clues point to the mysterious birthmark on the back of her neck. In the process of tracing the truth, she joined hands with the taciturn private detective Gu Chen, but she didn't know that there was a pair of eyes in the dark controlling everything...
