The first four episodes are pure visual music, animation serving the soundtrack instead of the other way around. After that, the plot collapses into confusion and never recovers. But those opening episodes hit like nothing else on TV, where every frame exists to make you feel what the music feels.

A black meteorite crashes into the world, unleashing grotesque monsters called D2 that are drawn to melodies. In the aftermath, music becomes humanity's greatest liability. Playing any tune is banned to prevent more deaths, and by 2047 a ruined America still lives under that prohibition. The world grows darker without the melodies that once gave people hope. But resistance emerges: young women called Musicart who embody pieces of classical music and wield humanity's great operas and scores against the D2, guided by partners known as Conductors. After a sudden D2 attack, aloof piano prodigy Takt Asahina becomes a Conductor bound to the Musicart Destiny. Together with Anna Schneider, who lost her younger sister in the same incident, they set out on a dangerous journey to the Symphonica Headquarters in New York City to stabilize their pact. Takt longs to play piano again, while Destiny is driven to destroy the D2.