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

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.

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.

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