It follows the people who recall their experiences as victims of violence due to the mysterious serial killings that begin when they receive a message from a friend from 20 years ago. Through these characters with tragic fates, the drama touches on the origin of school violence and the violence that pervades modern society.Kyung Min lives with the trauma of the school violence he experienced 20 years ago, and an unexpected case causes his hidden emotions to reappear. Meanwhile, Jong Suk receives a mysterious message sent by the friend from 20 years ago. That leads him to remember the school violence that took place back then. Chasing the mysterious message, he tries to stop more murders.Adapted from the animated film "The King of Pigs" (돼지의 왕) by Yeon Sang Ho (연상호). Watch drama online for free.