Arika Mamiya, the face of the idol group Lyrical Trick, suddenly disappeared without a trace one day. Now it has been over a year since then and her disappearance remains a mystery. Meanwhile, in a bid to promote the group, LT decides to hold an audition for the third generation members. Among the candidates is a blond girl named Nana Miyajima, who stands out from the rest of the crowd. It turns out she is actually Arika's best friend who has infiltrated the idol group to uncover the truth behind Arika's disappearance!