Kousei Arima, once a piano prodigy, is now haunted by his past. The loss of his mother left him unable to hear the sound of his own playing, effectively ending his musical career.
He lives a muted life with his friends, content to avoid the world of music that once defined him.
However, his monochrome existence is disrupted by the arrival of Kaori Miyazono, a vibrant and unconventional violinist. She pulls Kousei back into the world of performance, asking him to be her accompanist.
As they collaborate, Kaori challenges Kousei to confront his trauma and rediscover his passion for music, promising to bring color back into his life through their partnership.