Ji-soo (Bae Jong-ok) is an unassuming housewife leading a happy life with her college professor husband Joon-pyo (Kim Sang-joong) and their son. But trouble lurks when Ji-soo's widowed friend Hwa-young (Kim Hee-ae) accompanies Ji-soo and her family on a trip and secretly begins a love affair with Joon-pyo. One day, Ji-soo hosts a barbecue party at her house and invites Hwa-young and her sister Eun-soo (Ha Yoo-mi). Besieged by passion, Hwa-young and Joon-pyo end up making out inside the kitchen, but soon get caught red-handed by Eun-soo. Shocked and sickened to her stomach, yet nervous about what her fragile sister might do if she ever finds out, Eun-soo threatens Hwa-young and Joon-pyo to end the affair immediately. But truth has a way of slipping out, and Ji-soo's perfect life comes crashing down when she learns that her husband is having an affair with her friend. In the aftermath of the revelation, the psychological warfare begins, and to retaliate, Ji-soo decides to have an affair herself with her old college friend Seok Joon (Lee Jong-won).
