Ja-young has just given up civil servants' exam that she's been preparing for 8 years. When she's lost in her life, she gets to know Hyun-joo, a female writer and an amateur runner, who is full of life. Drawn by her vitality, Ja-young takes on running in the hopes of becoming like her. Doing a part-time job and running with Hyun-joo after work, Ja-young slowly rebuilds her body as well as her life. But soon Ja-young notices that Hyun-joo's life is also full of anxiety. Hyun-joo's depression leads herself to death in front of Ja-youngs bare eyes, and Ja-young spirals into shock. Now Ja-young struggles to find her own way as she struggles to deal with Hyun-joo's death.