On a mission to clear his name, Jang Ho-jae searches for a mysterious woman. On the job, Chae-ok encounters a familiar person from decades ago.

While looking for the same person, Ho-jae ends up saving Chae-ok, who's being chased by a mysterious being. Ho-jae begins to wonder more about his past.

In his effort to save Chae-ok, Ho-jae makes a momentous decision. Having sustained severe injuries, they must battle through a treacherous escape.

An unlikely acquaintance becomes Tae-sang's ticket out of the hospital. After a touching reunion, Tae-sang and Chae-ok encounter a transformed Myeong-ja.

Chae-ok agrees to work with Ho-jae to find Seung-jo, but they soon find themselves in peril. Meanwhile, Chae-ok's monstrous instincts begin to surface.

Yoon Chae-ok and Yoon Jung-won find a lead on Myeong-ja, leading them to a hospital. Soon, a calamity traps the two inside, leaving Tae-sang concerned.

Tae-sang decides to reenter the hospital, but discovers that Ryu Sachimoto is nearby. At the hospital, Chae-ok and Jung-won devise a risky rescue plan.

Reunited in their search for Myeong-ja, Tae-sang and Chae-ok attempt to also save other survivors. But soon, the monster makes itself known.

Tae-sang steadfastly remains to save Chae-ok and the captives. On a mission to find her mother, Chae-ok learns the grisly truth — and confronts the beast.

After a series of grisly deaths, Ishikawa finds Myeong-ja in her new state. Tae-sang shares a tender moment with Chae-ok, unaware of her hidden plan.

Ho-jae tries to piece together everything that has been hidden from him. Chae-ok discovers that the atrocities of the past continue to the present day.

After a test subject wreaks havoc in public, Jeonseung Biotech goes into damage control. Fate drives Ho-jae and Chae-ok to confront the company head-on.

As Ho-jae's enemy threatens to hurt those closest to him, he risks everything to protect them. Will he survive the ferocious beasts and save Chae-ok?

With only 10 minutes to act, Tae-sang and Chae-ok risk it all to get everyone to safety. But just as all goes to plan, one of them may not get out alive.

After coming face to face with the creature, Tae-sang and Chae-ok get captured. But as one plans his escape, the other stays to find a person dear to her.

In order to rescue Chae-ok and stop the atrocity, Tae-sang and Jung-won forge a plan. But just as the coast seems clear, Yukiko Maeda stands in the way.

Facing financial ruin, Jang Tae-sang agrees to track down a missing person — but two figures trail him. Meanwhile, sinister operations occur underground.