In Paris, music is everywhere, especially at the prestigious Conservatoire Eurydice. But does Ariane belong there? She doubts not only her talent but also her sanity: night after night she is startled awake by a melody that is not there. And why does she feel the urge to intervene when an unknown boy is mugged?

She discovers a startling truth: that Songs of Strength are the only defense against an ancient evil. A threat that could change everything is haunting the streets of Paris.