One night, a black meteorite dubbed “The Iron Meteorite of the Black Night” fell to Earth and forever changed the world. The meteorite gives birth to D2, grotesque monsters that quickly start overrunning the world. They are drawn to melodies, their only weakness, and before long music itself is banned.

However, there are some who stand up to the D2 — Musicart, young women who draw strength from music. Within them reside the scores of mankind’s greatest operas, which they use to destroy the D2. People called Conductors command the Musicart and lead the fight against the D2.

The story takes place in the year 2047 in a war-battered America due to the ongoing conflict with the D2. It follows the Conductor Takt and the Musicart Destiny as they journey to New York. Takt yearns for a world where music’s light can shine again and Destiny hopes for the annihilation of the D2.

Do the melodies they play embody delight or despair?