The backstory of Thundercats

A small group of survivors flee their disintegrating world Thundera and crash on a planet called Third Earth, where subsequent episodes take up their adventures trying to adapt to their new home while fighting baddies. Our main cast includes Lion-O, the main hero and wielder of the magical Sword of Omens, his Obi-Wan-like mentor Jaga who dies en route to Third Earth but appears in a ghostly form, Lion-O’s mentors and friends Tygra, Cheetara and Panthro, Lion-O’s old nursemaid Snarf, and the mischievous thunderkittens Wilykit and Wilykat. But the Thundarians have been pursued to Third Earth by the evil mutants of Plun-darr, led by the lizard S-s-slithe. To top it off, a mummified sorcerer named Mumm-Ra covets the Sword of Omens and frequently attacks the Thundercats to get the magical item, although after a while he’s pretty much obsessed with destroying the cats altogether.

The first few episodes have the Thundercats establishing themselves on Third Earth. From there, the bulk of the first season usually featured stand-alone episodes in which Mumm-Ra and/or the mutants hatch a new plan to get rid of the cats, or the Thundercats will run into some new problem or meet a new ally. The second season debuted with a five-parter in which three new Thundercats, Lynx-O, Bengali, and Pumyra, are discovered hiding on Third Earth. In the subsequent five-parter “Mumm-Ra Lives!” an ailing Mumm-Ra assembles a new group of villains called the Lunatacs to take on the Thundercats.