24-year-old Jung Jae-hwan, who brutally murdered his friend in his own home and then wandered the streets naked and covered in blood, has had his identity disclosed. Appearing on the SBS YouTube channel "Discovery of Knowledge," profiler Bae Sang-hoon described the murderer, Jung Jae-hwan, in one word: a "predator." We heard from profiler Bae Sang-hoon about how he could commit such a horrific act against a friend, and whether his bizarre behavior after the murder was a calculated move to claim mental instability, as suspected by the bereaved family.

(Planning: Kim Soo-hyung, Host: Jeong Yu-mi, Writer: Park Jung-rye, Editing: Kim Bok-hyung, Kim Hye-ju, Camera: Kim Sang-yoon, Hwang Se-hoe, CG: Jung Yu-min, Director: Jo Do-hye, Produced by SBS Digital News)