Jung Woo and his team have been investigating a serial bank robbery case for months, but they're told to dig into the so-called forewarned murder case. Unwillingly, they go to a club where the forewarned victim is supposed to be.
Jung Woo decodes the messages that the murderer sent and finds a lead. She figures out one common factor among the victims- they were all smiling the moment they died.
Jamie finds Jung Woo suspicious as he seems to be hiding a secret. Despite the events that make Jung Woo suspicious, Hye Won puts her full trust in Jung Woo. Another forewarning arrives!!
Jung Woo and Jamie find out that they're both from White Night Village. Jung Woo acts like White Night Village has nothing to do with the forewarned murder cases, but Jamie thinks differently.
Jung Woo saves the people who were trapped in the fire and instantly becomes a national hero. Jamie wakes up in the hospital and she's about to receive treatment by force.
Everyone including Hye Won is shocked by the fact that Jung Woo is the culprit of the forewarned murder cases. For those who know the truth behind White Night Village are going after Jung Woo.
The truth behind the forewarning murders starts to come up to the surface. Jamie and Hye Won keep following the evidence related to what happened in White Night Village 28 years ago.
Jung Woo continues to search for the secret lab. He runs into kids at an orphanage who talk about several kids being adopted by new families at the same time. Jung Woo thinks there's something fishy going on in that facility.
Jung Woo witnesses that a group of children is forced to get in a black van in front of Seoul Hangang Welfare Center and taken to somewhere, and he starts to follow the van.
Jamie sets off for White Night Village with Ji Wook to recollect her memories of what happened in the village. But then, a new warning arrives at Ji Wook's office.
Jamie finally arrives at the very place she abhors to even stay for a second. At the White Night Village, she and Ji Wook search for clues that might trigger Jamie's lost memories.
Jamie realizes that Jung Woo is her twin brother, the so-called monster who saved her life. After saving Jamie, Jung Woo continues with the investigation to find the location of the secret lab.
