Jin-seok is married to Ha-kyeong, but their marriage suffers from sexual frustration and emotional distance. When Jin-seok's younger brother, Min-seok, comes to stay with them along with his beautiful and outgoing new wife, Se-hee, the close living arrangement causes immediate tension. As Jin-seok becomes fixated on his new sister-in-law, Se-hee, and Ha-kyeong finds herself drawn to Min-seok, secret desires and taboo boundary-crossing lead to chaotic extramarital affairs within the household.