Much to her delight and surprise, Haruka was selected to become an "idol." Little did she know what she was getting herself into; rather than singing and dancing, she actually is employed by a secret organization that protects the Earth from "drops" (falling fragments of the destroyed moon) using giant robots called "iDOL," piloted by girls called "iDOL Masters." As she meets new friends and tries to adjust to this new life, a hostile organization that also utilizes iDOL emerges and attacks her in an effort to capture her iDOL, Imber. Can Haruka accept her new responsibilities, get along with her new peers and Imber, and do her part to protect the world?