While they are playing hide-and-go-seek, Trumpee, Snaree, Pino and the Xilo brothers end up in a cardboard box. It’s very dark inside, and there’s a funny echo. They are scared, but run off to Maestro Nomo’s house, and he reassures them. It’s just the sound waves bouncing around inside the box. The Meloditties go back inside the box and have fun making echoes.