Red Balloon

Eun-kang is Ba-da's lifelong friend of 20 years. She helps Ba-da, a jewellery designer, by doing odd jobs for her. When Eun-kang's boyfriend, Tae-ki, whom she had been taking care of for four years, passes the civil servant exam, Ba-da and her husband, Cha-won, take Eun-kang and Tae-ki to a luxury vacation house to celebrate. However, Eun-kang's hidden desires slowly begin to show.

Eun-kang goes swimming in the pool after becoming frustrated from an argument with Tae-ki, and Cha-won watches her from a distance. Meanwhile, Ba-da and Cha-won go through a rough patch due to Cha-won's parents. Later, Eun-kang dresses up to see Cha-won when Tae-ki pushes her away.

Eun-kang and Cha-won ignore Ba-da's calls and spend time together. A falling apart between Cha-won and Ba-da begins due to Cha-won's mother, which Ba-da can't take any longer. Meanwhile, Eun-san and Nam-chul have dinner together after working overtime, and later, Eun-san witnesses Tae-ki cheating on Eun-kang.

Eun-kang and Tae-ki's relationship becomes worse after Tae-ki meets her parents. Although Eun-kang desperately tries to hold on to Tae-ki, it's no use. Tae-ki even goes to see Ba-da and Cha-won and tells them about the breakup. Meanwhile, Cha-won's patience gets pushed to its limits as the clash between Ba-da and his mother deepens.

Eun-kang's family goes after Tae-ki for revenge after learning their wedding got canceled. Nam-chul lets out all the sorrow and pain he has been holding at Mul-sang, and Eun-san worries more about Nam-chul as she learns more about his inner feelings and his life with his in-laws. Meanwhile, Eun-kang, who has broken up with Tae-ki, makes a big decision.

Nam-chul's sudden demand causes a stir among the family members. Ba-da finds out that Gong-ju and Eun-kang met separately, so she asks Eun-kang what she said about her to Gong-ju. Eun-kang decides to show up at Tae-ki's wedding in a white dress. Meanwhile, Eun-san feels strongly attracted to Nam-chul who keeps making her worry.

Eun-kang and Cha-won spend time together at the beach in Sokcho. When Cha-won returns home from Seocho, he gets into a big fight with Ba-da about his mother-in-law. Meanwhile, Nam-chul and Eun-san become more affectionate and develop feelings for each other after sharing a kiss. However, one day, Mul-sang visits the office and notices a ginkgo tree leaf on Eun-san's desk that he had found in his camper.

Cha-won becomes confused when he learns about Ba-da's secret, and to make matters worse, the police visit his house. Later, Ba-da goes on a short getaway with her mom and runs into an old friend. However, a strange atmosphere flows between them. Meanwhile, Mul-sang makes a surprise visit to the company while Nam-chul and Eun-san are together, and in the end, has a deep talk with Nam-chul.