Song-hee is raised by her father, who was once a promising violinist. After he passes away, Song-hee is left a Stradivarius violin. Her classmate, Soo-wan, tells her that if she makes a wish when Jupiter meets the Twins, the wish will come true in twelve years, when the stars meet again. Twelve years later, Song-hee works as a kindergarten teacher and Soo-wan is a promising international lawyer. His fiancee, Yoo-jung, is a renowned violinist who was Song-hee's childhood friend and her father's best pupil. Song-hee is dismayed to hear of their engagement and impulsively suggests giving the Stradivarius to Yoo-jung, who would do anything for it, if Soo-wan will date her for a week. The plan is sealed, and as the two old friends begin their time together, Soo-hee starts to feel a warmth from Song-hee that was missing from his relationship with Yoo-jung, Song-hee and Soo-wan have a wonderful time recalling their past, but soon Soo-wan is scheduled to leave with Yoo-jung to study in America. Christmas is coming closer and Song-hee is determined not to lose her love.