Armstrong Stewart is struggling to keep up in school, convince the love of his life that he actually exists and keep in the good graces of his over-protective mother.

So when a maniacal, foam-mouthed beast chases him home on Halloween night, it is definitely not the added stress he needs in his life.

And the beast, it turns out, comes bearing a message.

There is a world beyond the land of humans, connected by portals spread around the globe.

A kingdom of Monsters.

It falls to the Keepers of the Gates, a group of half-monsters, to shoulder the awesome responsibility of keeping the Human Realm and Monster Realm safe ... and separated.

And now, whether they succeed or fail will fall to their newest member

Armstrong Stewart.