While he is heard singing Kuzco's theme "Perfect World" (which is the opening song), the Theme Song Guy doesn't appear on screen until the verse "Oh, yeah!", where he pops out of a large cake and sings about Kuzco who explains that his palace is under his command. He next appears continuing the song Perfect World after one of Kuzco's guards expels Rudy for "throwing off Kuzco's groove" from his palace.
The Theme Song Guy later appears in the end of the film where Kuzco becomes part of Pacha's family at the peasant's invitation after Kuzco changed his behavior from being a selfish tyrant to a caring, sophisticated man, still singing the reprise of Kuzco's theme "Perfect World".
The theme song person in this film is a Theme Song Girl. She sings "Be True to your Groove" and its reprise.
The theme song guy in this series was first introduced with black skin and hair and blue clothing in the episode "The New Kid." In later episodes, he has lighter skin and ginger hair.