실종사건의 용의자 김진우를 두고 갈등을 빚는 도원과 서경B.
도원은 자신의 작은 선택이 불러온 변화를 다시 뒤바꾸려 노력하고 서경은 오랫동안 자신을 괴롭혀 온 기억으로 고통스러워한다.
Jin Woo is the prime suspect in World B, and Do Won tries to figure out what has happened in this world. Seo Kyung seems to have a dark past in World B. Do Won tries to console Seo Kyung, but she doesn’t want Do Won to get closer. Jin Woo in World B did not have Do Won to stop him from his wrongdoings.
道元與B世界的書景因失蹤案嫌犯金振宇而產生了意見分歧。同時，道元正努力想要挽回因自己的一個簡單選擇所帶來的種種影響，而書景也被痛苦的回憶折磨著⋯
