In search of a new beginning, Lee Eun-pyo moves into a new apartment. She finds a note left by a former tenant to beware of Kim Yu-bin's mom.

Eun-pyo grows anxious when she sees her son, Jung Dong-seok, being disruptive in class. Byeon Chun-hui is appointed head of the PTA.

When Eun-pyo overhears that her son has been blacklisted by the school community, she decides to leave the neighborhood.

Eun-pyo tries to get Dong-seok into Yu-bin's group for the Rube Goldberg Competition. Seo Jin-ha's son, Henry Benuel, joins an opposing team.

As tragedy stirs the community, everyone tries to find out what happened while covering up their own tracks. Eun-pyo discovers a mysterious note.

As rumors grow more rampant, the moms are called to attend a group session at school. Jung Jae-ung faces hard truths as his wife's past comes to light.

Seeing that the case may soon come to a close, Jae-ung moves quickly to find the real cause of death. More gossip bubbles beneath the surface.

To protect her family and to climb the social ladder, Eun-pyo banks on Dong-seok's abilities. Kim Yeong-mi begins to suspect her husband.

Upon receiving a tip from an informant, Louis Benuel brings in Chun-hui and Lee Man-su for questioning. Dong-seok appears on a TV show for gifted kids.

Dong-seok sees a child therapist. Chun-hui deals with Yu-bin's unusual behavior. Eun-pyo reaches out to the one person who can help her son feel better.

Eun-pyo makes peace with a mom who is on the same boat as her. Chun-hui faces growing financial pressure. Yeong-mi discovers a secret folder.

Eun-pyo turns to Chun-hui with shocking news. When Chun-hui advises her to stay put and be quiet, it only fuels Eun-pyo's drive to expose the truth.

Chun-hui gives her husband an ultimatum, but struggles to find a way to support her family alone. Jin-ha's housekeeper entrusts Eun-pyo with a secret.

While out for drinks, Park Yun-ju witnesses a shady scene. When a message arrives on Jae-ung's phone, Eun-pyo makes an irrevocable decision.

Brought in for questioning by the police, Chun-hui names who she thinks is the real suspect. Henry makes a devastating confession to his father.