Hwa-ja has been raising three daughters alone in Busan after her husband passed away. One day, the second daughter Hye-young comes back to Busan after having continuous setbacks in Seoul. While spending time with her mom, she accidently sees a letter written in Japanese, which triggers her curiosity. She starts to ask Hwa-ja about her past life and gets to know new stories of her mother that she had never heard of.
| Actor | Role |
|---|---|
 Han Seon-hwaHye-young | Hye-young |
 Cha Mi-kyungHwa-ja | Hwa-ja |
 Han Chae-aHye-jin | Hye-jin |
 Song Ji-hyunHye-joo | Hye-joo |
 Go Jae-hyunGi-seop | Gi-seop |
| CChoi In-hwanPolice | Police |
 Oh Sang-yoonFriend | Friend |