Hakuo Gakuin is on the verge of closing down due to students transferring to rival school Seishikan after mysterious injuries happening to students who refuse to transfer. To protect the school and its students they hire Kojiro, a member of the Fuma clan of ninjas. After finding out that Seishikan has enlisted the help of the Yasha ninja clan, who had been rivals with the Fuma for generations, Kojiro gains the help of his fellow Fuma ninjas. Even though they are hired to protect the schools, the two rival clans vow to destroy each other once and for all so that only one clan remains.

The story begins when Ao opens a package that arrives at her doorstep. Inside the package is Gourai, a Frame Arms Girl: a small robot capable of independent movement. Gourai is a newly-developed prototype: a Frame Arms Girl equipped with an "Artificial Self," an advanced AI that gives her a personality. Ao is the only one that has activated her. Gourai begins to gather both battle data and emotions, starting a day-to-day life with Ao, who knows nothing about Frame Arms Girls. (Source: ANN)

Rick Wheeler was a police detective who got into a fatal car accident while pursuing the criminal Zoda. He was placed into artificial coldsleep for 150 years. Wheeler is brought back to life by Jody Summer and Dr. Stewart, who work with a group of good racers who try to keep prize money out of the hands of unsavory people like the Dark Million Organization run by Black Shadow and Deathborn.

One night, right before summer vacation, Manatsu Daichi, a second-year in high school, sees a weird round rainbow floating in the sky above Tanegashima and ventures there alone. He has seen this rainbow before. With the memories of his father's mysterious death and an encounter of a strange boy and girl, Daiji arrives on the island while the alarm of a building labeled Earth Engine is going off. Someone asks him if he is a captain, just as robotic intruders from Uranus called Kill-T-Gang arrive. The battle around the shining stars is about to begin.