A new Getter robot is piloted by three youth as they combat the evil terrors that plague the world.

Duke Fleed is a survivor of the Fleed Planet who has escaped to Earth. Onboard a mysterious spaceship, he is raised by Dr. Umon as his adoptive son, and becomes known as Daisuke Umon. Years after his arrival, he's faced with the threat of King Vega and his army, who want to conquer the Earth. With his friends Koji and Hikaru and later his younger sister Maria Grace, Duke decides to fight back using his best weapon - the almighty Grendizer.

For decades, the Abashiri family has been one of the most powerful and feared crime families in the world. Led by the frightening Daemon Abashiri, the family prepares to perform their final, greatest heist. As the family makes their assault on a large bank, Daemon reveals that his youngest child, Kikunosuke Abashiri, is actually the first daughter born to the family in 18 generations—which is why he wants to end their life of crime. Much to Kikunosuke's displeasure, her father has arranged for her to study at the elite Paradise Academy, hoping that the school will shape her into a proper lady. However, when she arrives, she finds that the place is even more brutal than the life of crime she just left! How does Kikunosuke intend to survive in a school full of teachers who are hell-bent on killing their students?

Fear runs rampant throughout Tokyo with the revelation that demons in fact exist amongst us. Paranoia and the darker side of humanity boils onto the streets as people turn on one another, suspecting that anyone could in fact be a demon hiding in human clothing. Amidst the growing tensions, tragedy strikes Akira causing his mind to snap, retreating into his subconscious, allowing his Devilish alter-ego Amon to break free from Akira's cage of flesh and wreak havoc on both human and demons alike.