O Mundo dos Casados

Ji Seon-u's marital bliss shatters when she spots an unfamiliar strand of hair on Lee Tae-o's scarf. Suspicious, she tails him after work one day.

After making a discovery that shakes her to the core, Seon-u is thrown into a dilemma. Yeo Da-gyeong's visit to her hospital worsens matters.

A piece of unexpected news sends Tae-o running to Da-gyeong. Taking advice from a divorce lawyer, Seon-u begins gathering important evidence.

Min Hyeon-seo deals with the return of her boyfriend, who wants to cash in on her efforts. Son Je-hyeok puts forth a risky proposition to Seon-u.

While Tae-o tries to save his affair, Seon-u learns more of his secrets. They head to Da-gyeong's parents' home, where an uneasy dinner ensues.

Seon-u and Tae-o's fight turns nasty as they battle over divorce papers and for custody of Lee Jun-yeong, who struggles to process their separation.

Tae-o and Da-gyeong come back to town and throw an extravagant housewarming party. While everyone gossips about the couple, Seon-u grows anxious.

Seon-u is spooked by a series of strange incidents at home. In addition, she finds out that Jun-yeong has been hiding something from her.

Da-kyeong becomes wary of Tae-o's behavior. Before an important meeting with Yeo Byeong-gyu, Seon-u receives a panic-inciting package.

A series of incriminating photos threatens Ko Ye-rim's marriage. Reeling from a betrayal, Seon-u seeks retaliation by paying Park In-gyu a visit.

After Tae-o comes home in a questionable state, Da-gyeong snoops through his clothes. Hyeon-seo is convinced she knows the culprit's identity.

When Tae-o is taken by police for questioning, Seon-u does what she thinks is right for her family. Da-gyeong urges Jun-yeong to make a choice.

Seon-u is in the midst of considering job openings outside the city when she gets word that Jun-yeong has been involved in a fight at school.

With both Jun-yeong and her job gone, Seon-u finds herself completely alone. When she goes missing, Kim Yun-gi and Tae-o rush to find her.

Nearing the end of her rope, Da-gyeong demands the truth from Tae-o. Soon after, Seon-u shows her the upsetting reality of Tae-o's patterns.

Seon-u gradually returns to her normal life. One day, she comes home to find that Jun-yeong has disappeared — and all that's left is a note from Tae-o.