Centuries ago, the fiercest ninjas of the Iga clan face their toughest enemies - and they aren't from this planet! A fiery mass crashes in the forest and soon horrifyingly savage creatures reduce the warriors to tasty snacks. But these extraterrestrials have bitten off more than they can chew. Swords and throwing stars may fail against unearthly goons, but ninja skills don't stop at sharp stuff.