Overview
On the night that 17-year-old Dong-jun's only friend, Kang-hyeon, fell from a high place, Dong-jun made a choice that determined the direction of his entire life. Dong-jun's regrets and remorse following that choice made him experience life in three different universes. These are the various lives of the 42-year-old Dong-juns who live different lives in Seoul, Daegu and Busan 20 tears later.
| Actor | Age then | Age now | |
|---|---|---|---|
 | 37 | 39 | |
 | 26 | 28 | |
 | 29 | 31 | |
 | 23 | 25 | |
 | 23 | 25 | |
 | 47 | 49 | |
 | 52 | 54 | |
 | 26 | 28 | |
 | 42 | 44 | |
 | 38 | 40 |