The Bailey School kids are surprised when their weird band teacher comments that the classroom skeleton, Claude, can play music better than they can, and when everyone wonders who is playing the tuba, Eddie vows to find the truth.
Mermaid Echo is doing tail flips because she's going to see her favorite under-the-sea band, the Rays. They're performing for Pearl's birthday party and everyone at Trident Academy is invited except Echo's best friend Shelly.