Episode 1
Traumatized by a tragedy that keeps haunting her, Jin Se-kyung vows to keep her loved ones safe and plots revenge against the perpetrators.
Episode 2
Suspecting Se-kyung's role in the latest murder, Kang In-a gives her a warning. But as Se-kyung plans her next move, a surprising visitor greets her.
Episode 3
Ha Yun-sang's friends celebrate his sudden return, despite the mystery surrounding it. Meanwhile, Se-kyung realizes she's being watched.
Episode 4
Se-kyung confides in In-a about the ominous threats she's been receiving. The two later embark on a dangerous mission to confront the criminal.
Episode 5
Despite her recent win, Se-kyung still worries that the threat isn't over. Yun-sang receives an enigmatic proposal involving important missing figures.
Episode 6
Disorder during the joint memorial Mass leads to chaos at the church, increasing criticism and scrutiny into the whereabouts of Father Baek.
Episode 7
Se-kyung discovers more about a mysterious training center, and pleads with In-a to investigate it. They soon find darker secrets lie within the building.
Episode 8
In the aftermath of the raid, the group encounters pushback from authorities — but they uncover more disturbing details about Father Baek's activities.
Episode 9
Se-kyung and Yun-sang finally confront Father Baek, who in turn leaves them with a choice, forcing Se-kyung to ask Yun-sang an impossible question.
Episode 10
On the day of the evacuation, Se-kyung and her friends coordinate a plot to get the children to safety. But pandemonium ensues as the plane approaches.
Episode 11
Accepting the fate of the asteroid, everyone tries to carry on with their lives. But the harsh and grim realities of their last days set in.
Episode 12
With less than 20 days left, survivors solemnly brace for the asteroid. However, Se-kyung remains steadfast in her mission to protect the children.