The relationship of childhood sweethearts Cha Song Joo and Hang Jung Suh becomes complicated when Jung Suh's father remarries. Along with a new stepmother, Jung Suh also has a new introverted stepbrother, Han Tae Hwa and a scheming stepsister, Han Yuri. Gradually, Tae Hwa falls in love with kind-hearted Jung Suh and Yuri decides to pursue Song Joo. Nothing can shake the bond between Jung Suh and Song Joo, however, not even Song Joo's departure to study abroad in America. On the night of his return, however, Jung Suh is mysteriously hit by a car and believed dead. Having lost her memory in the crash, she is taken in by Tae Hwa, who relocates and gives her another name. Five years later, on the eve of his engagement to Yuri, Song Joo sees someone who looks exactly like his lost love Jung Suh.