107 years earlier, the Moon was obliterated in a colossal disaster that fractured Earth's former satellite into 81 quintillion tons of orbital wreckage. Yet, thanks to advanced science, the planet itself survived and today most people barely recall that century‑old calamity and its aftermath has faded into myth. That is why, when the adolescent Haruka Amami enters a casting for an initiative dubbed the Idolmaster Project, she believes she is auditioning to become a singing idol. In reality, Haruka ends up at a covert academy operated by the Mondenkind Agency, cohabiting with several other girls who have likewise been chosen to command an iDOL—an ultra‑sophisticated robot engineered to intercept falling moon fragments, her hopes were misplaced. However, the operators of the Mondenkind Agency are not exactly chivalrous saviors. Moreover, there is doubt over whether the iDOLs are merely machines. From almost the very first instant, Haruka feels emotions emanating from inside the iDOL named Imber.