The new rulers of Plun-Darr say they'll bring one of the Mutants home: whichever one of them activates a homing beacon that will blow up the ThunderCats. Now it's every Mutant for themselves as they battle it out to be the one to activate the beacon!

Mumm-Ra, the Ever-Living decides he'll nap for a thousand years, until the ThunderCats are long gone. But when he wakes up, he's shocked to discover that Third Earth is even more in love with them than ever.