Ever since his mentor?the original Demonkeeper? mysteriously disappeared, Nat has been in charge of the demons that live in his house. Most of them are just nuisances, but the Beast who lives in the basement is very dangerous. When Nat goes out one night, a clueless burglar breaks into the house and unwittingly sets the Beast free. Meanwhile, a vicious villain, the Thin Man, wants to use the Beast for his own evil purposes. Can Nat defeat the Thin Man and return the Beast to the basement without any major casualties?

Seattle’s demons are scared and wreaking havoc in the rainy city. They’ve burned their way through the Seattle underground, threatened to topple the Space Needle, and sent a twenty foot statue rampaging downtown. It’s up to Nathaniel Grimlock, the teenage Demonkeeper, to control them, but when he discovers what’s stirring them up—a legendary monster known as the Demoneater—he finds that he’s in over his head yet again!

Seattle’s local Demonkeeper, Nathaniel Grimlock, is lost at sea. In his absence, the demons have taken over the city! It’s up to his delinquent apprentice Richie and Nat’s two competing girlfriends to prevent Seattle’s destruction until he can find his way home to face the most powerful demon of them all.