A public service worker at Oksu Station witnesses a shocking incident and recruits his friend to help uncover the truth behind the station's mysterious happenings.

Do Won and Seo Kyung both lose their fathers on the same night 12 years ago. In the present day, Do Won is a police officer and Seo Kyung a prosecutor. The police discover several skeletons on the train tracks at Mukyeong Station, which has been closed for five years. Do Won heads to the station while chasing a key suspect.

Through the course of their lives, a man and his first love are repeatedly separated from each other because of circumstances out of their control.