Lion-O struggles with his destiny to become the next King of Thundera, as chosen by the Sword of Omens. Meanwhile, festivities are held to celebrate General Grune’s return to the Cat Kingdom. An unforeseen betrayal by a former comrade brings destruction upon the Cat Kingdom. While King Claudus leads the fight against General Slithe and his lizard army, the evil sorcerer Mumm-Ra attempts to seize the Sword of Omens.