Jack’s friends make a startling discovery: they may not be the last kids on earth, after all. This is great news for everyone… except Jack. Once they’ve found other humans, his friends won’t stick around for long! Jack’s only hope for keeping things the way they are is to prove that everything here is perfect, life is crazy fun, and nothing else could be any better. After all, they live in a mind-clobberingly cool tree fort, speed through town playing real-life Mario Kart, have a crew of monster buddies, and battle zombies on the regular. That's as good as it gets!
 
One problem: it’s hard convincing his friends that everything is great when they’re being hunted by a monstrous Nightmare King and an ancient evil who won’t rest until Earth has been devoured. Crud! Maybe life after the monster apocalypse is more complicated than Jack thought…