Dongsoo leads a solitary life, spending his time uploading music to the internet. His ordinary life is upended when he is kidnapped by an organ hunter, who takes out one of his eyes. Soon, Dongsoo is sharing the vision of someone who got his eye. Through the connected vision, he learns that the taker is a notorious serial killer, and pursues the murderer to get his eye back.

When a software developer creates a dating app that a serial killer uses to find his next targets, she’s drawn into a dark world of romance and murder.