Air date: 2021-12-24

Runtime: 51 min

Director Choi's briefing about the mission leaves Song Ji-an displeased. Reaching the research station alone proves no easy feat for the crew.

Air date: 2021-12-24

Runtime: 47 min

The crew's initial findings are at odds with their knowledge of the research station. Split into threes, the members set out to look for the sample.

Air date: 2021-12-24

Runtime: 48 min

Ji-an's body cam captures a startling moment of life and death. Submerged in sweat, Gong Soo-chan shows worrisome signs of an unusual infection.

Air date: 2021-12-24

Runtime: 45 min

Han Yun-jae updates the director and gets access to a restricted area. The crew learns of the sample's powers and the true motive behind their mission.

Air date: 2021-12-24

Runtime: 40 min

Recalling her sister's encrypted message, Ji-an searches the database for Luna. A young intruder and a double-crosser emerge from the shadows.

Air date: 2021-12-24

Runtime: 44 min

E2, Ryu Tae-suk and the samples go missing. Seeing a familiar name on the intruder, Ji-an follows her down the vents for answers.

Air date: 2021-12-24

Runtime: 40 min

Ji-an opens a hard drive that chronicles Song Won-kyung's life and work on the station. Meanwhile, others uncover the remains of the experiment.

Air date: 2021-12-24

Runtime: 48 min

Racing against time as the research station falls under destruction, the surviving crew members decide on the fate of the mission — and their own.