Terminally ill young woman, Lee Bom Yi, is able to extend her life when she undergoes a heart transplant operation. She embarks on a new life, living each day to the fullest and positively, for the person who donated their heart to her. Then one day she meets Kang Dong Ha, CEO of Hanuiron and the widower of the woman whose heart she received. Since he lost his wife in an accident, read morehe has raised his two children by himself. They begin falling into a special kind of love, based on the unique subject of 'cellular memory' (medical term, a symptom where recipients remember the habits or personalities of the donors and since a body's cells store memory independently from the brain, it leads to an organ transplant's recipient to form new habits similar to the donor).
On the other hand, Kang Dong Wook is a cardiothoracic surgeon and conflict arises when his first love, a beautiful, sensible and eloquent woman, falls in love with Dong Ha, his hyung. Bae Ji Won wants the widower for herself and she’ll do her best to redirect his attentions. She’s a cold hearted and sharp-thinking team lead in the PR department of the hospital and a favorite of hospital chairman Myeong Hee.