Seventeen-year-old Alex begins questioning his sanity when he catches sight of a gremlin one night. Unfortunately for Alex, the sighting is only the first of many. Soon Alex is seeing gremlins at school, at home, and throughout his neighborhood.

The gremlins are among thousands of creatures released from Pandora's Box millennia ago. They now live among us, invisible and sowing chaos. They live by feeding on humanity's vices.

Alex's ability to see them has caught the interest of several long dead heroes who are searching for a new warrior to train. With the aid of several beings from the Natural World, they hope to drive back the demons and restore hope in the world.

But can Alex manage the sacrifices that will be demanded of him?