A woman who lives each day to fullest with a second chance.

A man who struggles to move on from his first love.

Song Jihyun was once a terminally ill patient, but was given a second chance after getting a heart transplant from a donor, now she lives her life to the fullest each day. Do Kyungsoo was a heartbroken man who was still unable to move on from his fiancee who died in an car accident. When the two meets, the two of them were immediately drawn to each other. Kyungsoo began to see smiliar traits to his first love in Jihyun and he question whether he fell in love with her or the fact she reminds him of his first love. Similiarly, Jihyun falls in love with Kyungsoo, unbeknown to her that Kyungsoo's fiancee was her donor.