Deep in a peaceful forest, a tiny hedgehog hears a river humming gentle lullabies each night. Curious, the hedgehog ventures out to find the source of the lovely music. On the journey, the hedgehog meets fireflies that glow with kind words, an owl who tucks the forest to sleep, and a family of deer who bow as the hedgehog passes by. Finally, the hedgehog discovers that the river’s song comes from smooth stones that chime together under the water’s surface.