Archivist Li Yanran never thought that those dusty files would come back to life. When she came into contact with the files of an old case, she and detective Chi Nan fell into the time and space where the case occurred - they became "outsiders", able to see the tragedy that was about to happen, but unable to intervene directly.
The only weapon is the ending hint in a few words in the dossier.
From the case of corpse dismemberment on a rainy night to the case of serial disappearances, the two traveled back to the scene of the murder again and again, fighting against the murderer for time in an attempt to change the fate of the victim. At the junction of reality and illusion, Li Yanran's calm restraint and Chi Nan's passionate impulse collided with each other, from strangers to tacit understanding, from comrades to the deepest bond with each other. But every time the past is changed, the reality file will also be distorted. They gradually discovered that there was a larger shadow hidden in the darkness of all cases - and those files seemed to be the "script" prepared for them.
When good intentions become traps and there is a deeper evil hidden behind the truth, can they still keep each other's original intentions?
