Neurosurgeon Tae-ju clashes with his wife Se-yun, the board director of his hospital. Tae-ju demands a divorce. But the next day, his wife vanishes.

Taeju goes to his in-laws for help, only to run into detectives. Another call with no caller ID comes through. Seyun wakes up in a strange room.

Suhyeong gives Taeju an ultimatum: show up at a specific place and time to save his wife, so Taeju makes a daring escape from the police station.

Taeju makes a desperate escape. His hope of seeing Seyun again is short-lived when he's faced with a photo of a brutally murdered woman.

The kidnapper agrees to Taeju's deal. This could be the last chance to save Seyun. Meanwhile, Suhyeong has been following Taeju from a distance.

Having obtained the kidnapper’s home address, Taeju hides in a doctor's office from detectives, only to come face-to-face with an unexpected person.

Taeju and Seyun fight for their lives, but Noh Manhui's ferocious determination to kill pushes them to the brink.

Jeongsu's attempt to kill Gyeongae fails. But Taeju is haunted by Jeongsu's claim that he was "just following orders."

Noh Manhui and the mastermind behind him remain at large. Taeju poses as Gyeongae’s doctor to uncover the truth. Jang discovers an unexpected clue.

After a tense standoff, Taeju and Manhui each uncover pieces of the truth. Meanwhile, Seyun learns the full story of that nightmarish day.

Taeju discovers who's really behind the case, but he's stuck without proof. A fire alarm goes off at night, throwing Woori Medical Center into chaos.

Manhui and Chiung appear before Taeju, and the three head to the care home where Gyeongae is, each with their own goal.