When intergalactic rock star Sky Rocker plays a concert at the Cosmic Coliseum, Judy Jetson and her friends go into orbit. Starry-eyed Judy gets to meet her idol and gives him a song which she has written just for him, "Rockin' Round the Galaxy". But also at the concert are henchmen of the evil, music-hating Felonia. They are carrying a secret code that will unlock the powers of the Mental Flosser and enable Felonia to control the universe and banish music forever!