Jina is the top employee at a credit card company call center. She avoids building close relationships, choosing instead to live and work alone – until she is suddenly tasked with training a new recruit.
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.
Green is a professor in a long-term relationship with her lesbian partner. Failing at preparing the deposit for the house and Green being laid off for helping her homosexual colleague, the only option they can choose is to move in with Green’s mother. As their awkward stay prolongs, the mother drives all her energy into her job as a caregiver.
