Reinya appears to be an ordinary girl working at a convenience store but she is in fact, the Phantom Thief Reinya. Together with her assistant Chūtarō in their secret hideout right below the local convenience store, Reinya hatches plans to steal various treasures made of gold. They face an incompetent trio of a perverted police inspector, a policewoman who is a natural airhead, and a detective totally infatuated with Reinya, all of them in a police station beside Reinya's convenience store.