Chen Shu, an ordinary courier, received an unusual express delivery while working the night shift. The sender field is blank, the recipient is himself, and the sending date is three days later. There was only a note in the package, which read in printed letters: "Don't open it, wait until I come to you." Chen Shu couldn't hold it back, and after opening it, he found an urn inside. There was a photo of him on the lid, and the date of his death was four days later. At this moment, clear footsteps were heard at the end of the corridor.
