Zach Darlington used to live in the world's most boring town--that is, until he buys a mysterious ring at a flea market, which suddenly causes the whole place to become overrun with monsters straight from the Jewish folklore his mother has shared with him and his annoying little sister, Naomi, all their lives.

When Zach discovers that the ring also grants him strange powers--like speaking to animals!--he becomes determined to figure out how to use these new powers to end the bullying he's been experiencing at school. But his plans are upended by an unexpected visitor: the King of Demons, disguised as a boy named Ash with the help of Zach's sneakers covering his taloned feet!

Surprisingly, the King of Demons isn't the scariest creature attracted to the ring. A secret society emerges from hiding, intent on using Zach and the ring to summon three monsters--the Behemoth, the Leviathan, and the Ziz--to fulfill a prophecy spelling doom for all who walk the Earth.