Arrogant and self-important musical director YU Il-han (KIM Rae-won) is full of false confidence and given to groundless boasting. Once a promising director, a miserable box office failure has prevented him from getting any work except for a children’s musical. A win could mean taking a blockbuster production called “The King of Joseon” to Broadway. Live on the show Il-han blindly selects Glory (JI Dae-han) as his partner by listening to the child sing, only to discover that the contestant does not look like a Korean. Despite possessing an angelic voice, Glory cannot possibly compete against children groomed from the crib to be musical stars. The boy endures the grueling training and slowly wins over the hearts of those around him, including Il-han’s. But can the unconventional duo move the hearts and minds of the audience and judges when it counts most?