The series consists of mostly stand-alone episodes which retell different fairy or folk tales. Despite the title, they are not all based on fairy tales collected by the Grimm Brothers.

The Gaira aliens, hidden in the Arctic, plan to conquer Earth. Captured and forced to work for the aliens, Dr. Yan creates the ultimate weapon, a transformable aerial robot called Groizer X. Entrusted to his daughter Rita, Groizer X escapes the clutches of the Gaira and lands in Japan, where pilot Jo Kaisaka meets a wounded Rita. Taking up the controls of Groizer X, Jo and Rita fight against the Gaira invasion.

Generations have passed since the war with the Space Monsters started, and none remain who know how it began, with even records of those times being scarce. It is a lost cause, but humanity still fights against them, relying on the Topless: a group of elite space pilots with special powers that allow them to use the Buster Machines—the last hope against the Space Monsters. Nono, a girl from a remote Martian town, has heard tales all her life of the legendary pilot Nono-Riri, and wants nothing more than to leave her humble life behind and follow in the footsteps of her idol. Though she has no idea of the dangers that lie ahead, nothing will stop her from achieving her dream. While Nono is down on her luck, she chances upon the lonesome Topless pilot Lal'C Melk Mark, and decides to stake her entire future on following Lal'C, no matter the cost.

It is a harsh and barren wasteland, where the weak aren't allowed to dream. It is also a sacred land for true men, for there is no place a man can feel more alive. This is the Gun Frontier. Sea Pirate Captain Harlock and the errant samurai, Tochiro arrive in the United States on the Western Frontier. Along with a mysterious woman they meet along the way, the two friends challenge sex rings, bandits, and corrupt sheriff. They are searching for a lost clan of Japanese immigrants, and they will tear Gun Frontier from end to end until they find it. (Source: ANN)