100 years ago, titans suddenly appeared on Earth. Soon, human civilization veered on collapse due to the titans. Humans then built a giant wall to defend themselves. Within the giant walls, humans lived in peace, but, 100 years later, the giant wall is broken.
Description: Musical director Yoo Il-Han (Kim Rae-Won) is arrogant and has no qualms exaggerating the lengths of his talents. He was once a promising musical director, but, after the box-office failure of a big budget musical, he now works on children's musicals. Nevertheless, Yoo Il-Han dreams of one day working on Broadway in New York City. His big chance then arrives. A TV musical competition program is set out to select the main child actor for a big budget musical of King Jungjo from the Joseon Dynasty. The musical will be performed on Broadway.
The setup for the TV musical competition program involves five musical directors as they each select one child actor to mentor. The directors then train their  ... pupil and the TV musical competition eventually selects one child actor to play King Jungjo. Musical director Yoo Il-Han is one of the five music directors taking part in the television program. The first stage of the show involves each of the five musical directors turned away from the stage as they listen, but cannot see, various children auditioning for the TV program.
Musical director Yoo Il-Han then selects a child named Young-Kwan (Ji Dae-Han), who turns out to be a half Filipino-Korean child. Once the first episode of the TV show program ends, Yoo Il-Han berates an assistant director of the TV program. He's furious he was allowed to pick a child, that he assumes has no chance of playing King Jungjo and blowing his chance to work on Broadway. Making matters worse for Yoo Il-Han, Young-Kwan possesses zero dancing abilities. Unable to change his selection, Yoo Il-Han half-heartedly begins to train Young-Kwan. He then begins to see something special in the child.