Lee Bom Yi, a terminally ill woman, undergoes a heart transplant and begins living life to the fullest, honoring her donor. She meets Kang Dong Ha, the CEO of Hanuiron and widower of the woman whose heart she received. As they grow closer, they form a special bond, influenced by the concept of "cellular memory" — where transplant recipients adopt traits of their donors. Meanwhile, conflict arises with Kang Dong Ha's brother,
