One stormy night, a mysterious orchestra conductor comes calling on Harold to whisk him off to an opera in the sky! There, a handful of children are awaiting… the musicians of the storm! This orchestra’s job is to play melodies adapted to its audience’s tastes : a booming concerto for the old lady who loves thunder, and a gentle tune for those who are instead afraid of it. And over and through it all, the sound of rain… Hush! Let this secret symphony be your lullaby!