21-year-old pianist, Lee Si-yoon chooses to die pessimistically about his life that can no longer play the piano due to an accident, but he wakes up as Tatiana, a girl from a wealthy family who speaks a foreign language that he cannot understand. Is this a God-given opportunity? Or is it a curse? What's the big deal with the gender change? As long as your hands are intact, you can play the piano again! Let's make our dream come true as 'Tatiana'!