200-year-old Min Se-yeon (JiHyun) has managed to conceal her immortality, up until she meets Lee Jung-hoon (Ji Eun-sung), a social worker she saves from a traffic accident. Despite her wizened age, Se-yeon is fresh, beautiful and forever in her prime, but with immortality comes a price. Can Se-yeon and Jung-hoon defy time in the name of romance?