‘Ha Dong-Soo (Jung Hae-In) is part of a new human race called connect. The connect beings never die. One night, Ha Dong-Soo is kidnapped by a group of human organ traffickers. His eye is cut out from him. He soon sees something and realizes the man who has his stolen eye is a serial killer. Ha Dong-Soo is now able to see what the serial killer sees. He chases after the serial killer to stop him from killing anymore people. Meanwhile, Ha Dong-Soo’s stolen eye has been transplanted into Oh Jin-Seob (Ko Gyung-Pyo). Oh Jin-Seob looks a polite and competent employee at work, but he is actually a cold-blooded serial killer.