Betty Barrett is a typical 12-year-old girl who enjoys school, daydreaming about living in outer space, sci-fi movies and singing in her musical band, living in Moose Jaw Heights (a fictional suburb of Moose Jaw, Saskatchewan). Unknown to all of her friends and family, however, she is also a member of the Galactic Guardians, an elite team dedicated to interstellar crime fighting and law enforcement. As "Atomic Betty", assisted by her two allies; the alien pilot Sparky and a robot named X-5, she confronts the evil overlord Maximus I.Q. and his servant Minimus, as well as other intergalactic supervillains, criminals, terrorists, and gangsters. Despite being rather unassuming on Earth, Atomic Betty is a superstar throughout the galaxy and even has a crowd of people who consider her their role model.
In each episode, a crisis occurs somewhere in the galaxy, usually while Betty enjoys some tasks with her friends. Invariably, her wristwatch begins beeping, and she runs off alone to save the galaxy in her nice pastel pink-and-white superpowered Galactic Guardian battle suit, which allows her a wide variety of weapons, gadgets and supernatural abilities, such as flying. Accompanied by her crew, Betty takes over to fight the villains before returning home and mentioning her absence.