Kang Ji-Won (Park Min-Young) is married to Park Min-Hwan (Lee Yi-Kyung). Her marriage life is not going well due to her selfish husband and his demanding mother. Kang Ji-Won is the breadwinner of the family, while her husband Park Min-Hwan is unemployed and in debt. Kang Ji-Won also does all of the housework herself. One day, Kang Ji-Won learns she has cancer and she doesn't have much time left to live. Making things worse, she witnesses her husband and her close friend Jung Soo-Min (Song Ha-Yoon) having an affair. She gets into a physical struggle with the two of them and she is killed by her husband Park Min-Hwan. The next moment, Kang Ji-Won opens her eyes and finds herself in the past, 10 years earlier when she was dating Park Min-Hwan. She decides to change her life by making Jung Soo-Min marry Park Min-Hwan. Meanwhile, Yoo Ji-Hyeok (Na In-Woo) works as a chief in the same department as Kang Ji-Won. He has a crush on her and he slowly reveals his feelings to her. He also has a secret.