While burying one of the time capsules that transported the Thundercats to Third Earth, it smashes apart and Lion-O gets caught in its gases, making him younger and younger by the minute. The other Thundercats must find a way to reverse the process and realize the Cave of Time is the only way, but they must get Lion-O there before he "vanishes" from existence. Things get worse when the young Lion-O and Snarf are captured by the Lunataks.
Genres: Action & Adventure , Animation , Kids , Sci-Fi & Fantasy
Keywords: anthropomorphism , cat , clairvoyance , future , good-versus-evil , high-technology , magic , mummy , mutants , post-apocalyptic-future , pyramid , space , spaceship , super-speed , sword