Jang Sae-Byeok (Yoona), a very cheerful and positive girl, tries to find a new meaning in life after she receives an eye cornea transplant from another girl of the same age. To express thanks to the donor's family, Jang Sae-Byeok visits the donor's family of the dead girl, Na-yeong. But Na-Young's parents who even have no idea that their daughter was killed by traffic accident are shocked to fall in a faint. But as time goes by, Jang Sae-Byeok becomes close with Na-Young's family and the family, who become to be aware that Jang Sae-Byeok is an orphan, slowly accepts her as a daughter.