his series was based on the popular X-Men comic book series published my Marvel Comics, beginning in 1963. The X-Men franchise deals with mutants and their place in society.

In regards to Marvel canon, mutants are humans who are born with a genetic anomaly - which normally manifests in a person's early teens - that gives them some type of superhuman ability. In the scheme of the world's overall population their numbers are extremely few, but these people are seen by many normal humans as a potential threat to mankind; on the immediate level because mutants possess powerful abilities that could be used for great harm, and as a long-term threat as possible successors to homo-sapiens (mutants are termed "homo-superior" by some) on the evolutionary scale. At their most benign, normal humans fear and shun mutants. Some want mandatory registration and monitoring of mutants or to have them interned, while a few radical thinkers even call for extermination.

Wheelchair-bound Professor Charles Xavier believed that mutants and non-mutants could coexist in harmony. Himself a mutant with powerful telepathic abilities, he established the Professor Xavier School For The Gifted under the pretext of a private institution for talented individuals. The school secretly provided a haven for mutants and worked to educate them on the responsible use of their powers and to use those powers for the benefit of all mankind. With sufficient training, students graduated to the X-Men team, where they confronted the forces that would destroy the harmony Charles Xavier hoped to one day achieve. They protected mutants from persecution, and they interfered with mutants who would use their power to wage war on humans.

Storylines for the television series followed many of the same plotlines explored in the comic books. The lineup of group members in the comics was ever changing and the total number of past and present members was correspondingly large. The group's membership was shuffled somewhat in the animated series as well, but it focused on and maintained a core lineup throughout the show's five year run. Several of the comic's most prominent members - such as Colossus, Nightcrawler, Angel and Iceman - only made spot appearances, usually in a storyline similar to their original introduction in the comic book series. Membership in the animated series did, however, consist of several of the franchise's mainstays, along with a few characters who were popular but fairly new at the time the animated series was produced.

Of the X-Men team members, Cyclops was normally second in command to Professor Xavier. His mutant ability allowed him to store solar energy for discharge as powerful force beams that he fired from his eyes. Jean Grey had psychokinetic abilities that allowed her to move objects with her mind. She also had limited telepathic abilities. Beast was extraordinarily agile and had superhuman strength. His furry appearance belied his high intelligence. Wolverine had heightened senses and an accelerated healing ability. A lacing of indestructible adamantium was surgically grafted to his skeleton (he was also given two sets of retractable claws that disappeared into his forearms when not in use). Storm had the ability to control and manipulate the forces of nature, shifting weather patterns to suit her needs. Rogue had the power to absorb energy from other living beings. If her skin came into contact with someone else she absorbed their powers and their strength to be used as her own. The affects were only temporary depending on the length of time she remained in contact; too long, and they became permanent. One such incident gave her the permanent power of flight and made her indestructible. Gambit could charge objects with kinetic energy, so that when he threw them they exploded upon impact. He carried playing cards for just such a purpose. The youngest member, Jubilee, could generate multi-colored bursts of plasmoid energy, to hurl as a physical force or to short-circuit electronic equipment. A group member called Morph was created specifically for the animated series. He could change his shape to match the appearance of others. Morph appeared to die in the second episode, and was most likely created to establish a tone for the series that showed the very real danger inherent to the X-Men during their missions.

The success of the series opened the door to a run of other Marvel superhero cartoons - such as Spider-Man: The Animated Series, The Fantastic Four and Iron Man - that got away from the standard, lighthearted fare of previous superhero animated shows and tackled more adult-oriented themes.