Wang Ke, a cancer patient, has long harbored a deep grudge against Li Ruyi and Chen Yang for causing the death of his sister's family. Years later, he finally seizes the opportunity for revenge. In the dead of night, locksmith Chen Yang, after answering a call from Li Ruyi, heads to Room 1803 to fix a door lock. Wang Ke takes advantage of the moment to scare Li Ruyi on the 18th floor and punish Chen Yang before disguising himself in Chen Yang's clothes.