Seven years after the roundup in Vietnam, Ma Seok-do joins a new squad to investigate a murder case. He soon starts to dig deeper when he finds out the case involves a synthetic drug and a gang of thugs.

The ‘Beast Cop’ Ma Seok-do heads to a foreign country to extradite a suspect, but soon after his arrival, he discovers additional murder cases and hears about a vicious killer who has been committing crimes against tourists for several years.