After the murder of their parents, 11-year-old twin brothers Thor and Rai Klein are sent away from their home planet. They find themselves awakening on the terraformed planet of Chimaera, where carnivorous plants dominate and the few humans who live there are divided into four groups known as Rings. Soon after, they meet a young man by the name of Zagi, and the twins learn that only the Jyu Oh Sei—the one who conquers these four Rings—is allowed to leave the planet. Driven by the desire to return home and discover the truth behind the death of his parents, Thor resolves to survive in the harsh, merciless environment of Chimaera. However, he quickly learns there is more than meets the eye in this strange ecosystem. As Thor is swept up in the politics that entangle the Rings, he uncovers more about his parents' murder, and ultimately, humanity's fate as a whole.

Chase Suno and his friends, Jinja and Bren, are on a search for Chase's father, Jeredy Suno. However, they soon become involved in something else upon reaching their father's lab and becoming involved with an organism known as Monsuno. Chase, choosing to side with his father's work, denies S.T.O.R.M. access to the Monsuno and escapes. They are now on the run from the military organization, S.T.O.R.M., while still looking for Chase's father. However, a mysterious organization also has his eyes set on Chase and the group's Monsuno. (Source: Animeultima)

This is the condensed theatrical adaptation of the original TV series' first season.

Two years after the defeat of Galactor and the apparent death of Condor Joe, a cruise ship is attacked by Leader X, killing nearly everyone on board. One of the survivors, a young girl, is captured by X and rapidly aged into the bizarre, masculine-voiced villainess Gel Sadra. Though she has the appearance of an adult, Gel Sadra is not immune to throwing childish tantrums and behaving immaturely. In the midst of the revival of Galactor, the Science Ninja Team is called back into action, with a shady man known as Hawk Getz acting as the replacement for Joe. Getz is quickly revealed to be a Galactor agent in disguise (and had killed the actual Getz who was to join), and winds up killed by a mysterious feather shuriken. After hints spread in the first three episodes, Joe reappears in the fourth episode, having somehow survived his fatal injuries at the end of the first series, and rejoins the team. It is later revealed that he was rescued by an ex-Galactor scientist at the brink of his death, and was the subject of various cybernetic augmentations. Later in the series, a female scientist known as Dr.Pandora is introduced, who had lost her husband and daughter in the cruise ship disaster. Unbeknown to her, her daughter Sammie survived and is in fact Gel Sadra.