Arima Kousei, once celebrated for his victories in piano competitions under his mother’s rigorous guidance, earned the nickname “human metronome.” However, following his mother’s passing, he lost the ability to hear his piano’s music. His life takes a turn when he encounters Miyazono Kaori, introduced to him by his childhood friend Sawabe Tsubaki. Kaori, a spirited violinist, inspires Kousei to reconnect with the piano. Yet, unbeknownst to him, Kaori harbors a hidden secret.