While filming a documentary, Isoo receives a chilling, anonymous message: "Detective Jin. Let the game begin."

After a string of bomb attacks, Isoo flees to a safe house. The bomber's final message: "FINAL ROUND."

Isoo and Hyera investigate a haunted house tip. After an attack by an unknown assailant, they wake up to find themselves tied up inside the house.

Five bodies are found in the abandoned house. Looks like a meticulously planned series of murders. Violent Crime Investigation Team 1 begins the hunt.

A concierge is found dead in a hotel room on White Day. Could this be a crime of passion?

As Violent Crime Investigation Team 1 questions a suspect in the concierge murder, the hotel owner disappears. The team gives chase.

A magician dies in a mysterious fire during his act. Isoo and Hyera are stunned to meet a man with his exact face.

The boss of the Hammurabi gang emerges as a new suspect. Isoo devises a plan to confront him.

Hyera tells Isoo that she is hunting a serial killer after an arts student is found dead in a bizarre state.

Isoo works to decode a dying message with the victim's three friends serving as the main suspects.

Hyera finds Isoo at his house covered in blood next to a dead body, with all the evidence pointing directly at him.

Isoo and Hyera face a grim and chilling surprise when a mysterious large box containing a murder victim's corpse is delivered directly to their police station.

Isoo wakes up covered in blood next to a dead body, and the growing evidence places him right at the center of a murder investigation.

Isoo faces a major emotional and professional dilemma between protecting his family and doing his duty as a police officer.