The inhabitants of the earth Thundera evacuate before it's destroyed. They were chased by a group of mutants. All but among these escape ships had been destroyed. Only a little team of Thunderans (Thundercats) remained. With just half engine power had to set a route for the nearest planet. Jaga commanded their ship while another seven were in their tubes. Jaga expired in their journey to Third Earth along with also their ship crashed there. So on they made friends inside the area with several groups and a fortress was designed by them. Mummra the centuries-old embodiment of evil really are a continuing threat. But Lion-O, the new leader of the Thundercats, together with his weapon that the"Sword of Omens" can allow the Thundercats to own a standing chance.