As suspicion toward Gi Beom grows, Tae Joo is confused because the circumstances point to Gi Beom as the killer, but he hesitates to arrest him for some reason. After another murder case happens, he tries to find the missing Gi Beom to ask about everything, being sure that Gi Beom is the killer. Si Yeong, who was attacked by the killer, wakes up, and he reconciles with Tae Joo. But with the emergence of Si Yeong’s brother, the situation of the investigation unit becomes complicated.