Do Hae Kang (Kim Hyun Joo), is a successful lawyer, but she wants to become more successful. Due to her ambitions, her relationship with her husband, Choi Jin Uhn (Ji Jin Hee), deteriorates. At that his time, Jin Uhn meets Sul Li (Park Han Byul), who attends the same graduate school. Her personality is pure and enthusiastic, like his wife Hae Kang had in the past. Hae Kang then has an accident and loses her memory. She meets Baek Suk (Lee Kyu Han), and live as her younger twin sister Yong Gi.
