Back in high school, Jin Xiaozhen was a gifted pianist. So gifted, in fact, a young Yu Saisai would sneak into the piano room just to hear him play. Those small moments inspired Saisai enough to take up piano on his own. Now, eight years have passed since he last saw Xiaozhen. One night, Saisai finds himself in a foreign restaurant—literally. And then, on a cruise ship. What's happening?! As it turns out, the two have started trading places through teleportation! How did this start, how can they make it stop, and what does it mean for the future of these two fated souls??