S01:É01 - S01:E01 - A Closed Down Station and a Skeleton
Dead bodies in skeleton form are found in closed down Mugyeong Station. Do-won is on the case.
S01:É02 - S01:E02 - Truth of the Murder From 12 Years Ago
Seo-kyung finds the keepsakes that were gone 12 years ago at a murder scene in the skeleton.
S01:É03 - S01:E03 - A Reversible Death
Seo-kyung is murdered by the Mugyeong Station killer. Do-won sees someone unexpected at the station.
S01:É04 - S01:E04 - There's Another Me in This World
Do-won goes to World B and meets Seo-kyung. He's being chased as the suspect of a murder case.
S01:É05 - S01:E05 - Life and Death Crisscrossed
Do-won A starts looking for victims of World A in World B, then has an unexpected encounter.
S01:É06 - S01:E06 - Fate vs. Bad Luck
Do-won and Seo-kyung B are at odds over Kim Jin-woo, the suspect of the missing person case.
S01:É07 - S01:E07 - A Truth I Wish Were a Lie
The duo chases the culprit of the murder from 12 years ago. Do-won learns about Seo-kyung's past.
S01:É08 - S01:E08 - Another Me in Front of Me
Sung-wook falls in front of Do-won and Seo-kyung's eyes. Meanwhile, Do-won A encounters Do-won B.
S01:É09 - S01:E09 - Death of Another Me
Do-won's shocked to find traces of the culprit in Do-won B's body and learn about the serial killer.
S01:É10 - S01:E10 - The Only Evidence
Min-joon confesses that he was the real culprit of Mugyeong Residence Murder Case from 12 years ago.
S01:É11 - S01:E11 - Two Worlds Disconnected
Do-won and Seo-kyung waits for train 8210 but it no longer arrives. The two worlds are disconnected.
S01:É12 - S01:E12 - Terminal Station
Min-joon's anger towards Mi-sook begins to tighten Mi-sook's neck. Can Do-won save the day?