Kate and Mim-Mim know a special place filled with great music: Mimiloo! After Mim-Mim accidentally breaks a recording of the gang's favorite song, Kate, Mim-Mim, Tack, and Gobble head off on an adventure to the Singing Seas to find Callie so they can re-record her wonderful tune. When they arrive and discover that Callie's Mega Music Maker is broken, Kate leads her friends on a quest to fix the instrument.