File No. 13

Yuncheng has an unwritten rule:

On the 13th of every month, a bizarre case occurs in the district.

Surveillance screens go black, witnesses lie, and evidence disappears. In the end, the case can only be closed as unsolved.

Veteran detective Lu Zheng has never believed in the supernatural.

That is, until he inherited his father’s effects: a black notebook that could never be opened, marked with the number “13.”

From then on, every time the 13th comes around, he can see things no one else can:

Lingering images at crime scenes, the dying gaze of the deceased, and… people who should not exist.

“Dad, what exactly did you discover back then?”

When he finally uncovers the truth behind his father’s death in the line of duty, he realizes that…

Some files must not be opened.

Some rules must not be broken.

And some people should never have been forgotten in the first place.