Alexandra Graff, a Californian living in Paris, is a stained-glass artist whose synesthesia gifts her with the ability to see sounds in the form of color. When she’s commissioned to create glass panels for the new Philharmonie, she forms a special bond with the intriguing Halina Piotrowski, a famous Polish pianist. As their relationship develops, Alexandra shows Halina the beautiful images her music inspires. But when it comes to a lasting future together, will Halina’s fear of roots and commitment stand in the way?