Season 1

On his birthday, So Mun's struck by a strange burst of light that leaves puzzling changes to his body. He finds answers inside the local noodle shop.

The Counters give Mun an extraordinary surprise. While contemplating whether he wants to join them, he's given a taste of the action.

Lim Ju-yeon and Kim Ung-min notice something is different about Mun. Ga Mo-tak heads to the police station for answers about his forgotten past.

In a confrontation with violent bullies, Mun loses control over his rage — and must face the consequences. Mo-tak is reunited with his old cellphone.

Do Ha-na saves Mun from the attacks of a powerful demon with a malicious tongue. Kim Jeong-yeong helps Mo-tak look into his last detective case.

While the Counters attempt to keep the truth behind his painful past from Mun, he discovers a mysterious memory card among his parents' belongings.

During a trip into his most traumatic memory, Mun has his first encounter with Ji Cheong-sin. Later, he leads the Counters to a car junkyard.

Things get personal for Ha-na as she takes down a familiar demon. The team tries to locate a reservoir tied to a case Mun's father had worked.

Cheong-sin leaves Mun in a bad state, but Chu Mae-ok is determined to save his life. The Counters set out to make the mayor's corruption public.

Wi-gen calls for an action that could take everything away from Mun. When stunning news about Cheong-sin is reported, the Counters can't believe it.

The Counters struggle in a mismatched fight against an increasingly dangerous Cheong-sin and the other demons. Mo-tak's memories resurface.

A heartbroken Mo-tak and the team plot revenge against Shin Myeong-hwi and his collaborators. While carrying out their scheme, a human corpse turns up.

As Cheong-sin becomes nearly unstoppable, the Counters learn there may be a way to defeat him for good. Mo-tak gets justice for Jeong-yeong.

Myeong-hwi's son notices something about his father isn't quite right. When Baek Hyang-hui kidnaps a young girl, the Counters rush after her.

The team welcomes back a Counter who's been overseas. After confirming his suspicions about his father, Shin Hyeok-u goes to Mun.

The final face-off against Myeong-hwi tests Mun and the other Counters' limits. In Yung, long-awaited reunions take place.