Ever since he took a bite of a legendary dessert last summer, twelve-year-old Guster Johnsonville has never been the same. In fact, when a strange little man dressed as a conquistador comes clattering into the barn at the back of the Johnsonville farmhouse one afternoon, he forces Guster to face the truth: Guster is now the most delicious thing in the whole world, and a terrible monster is coming to eat him.

The monster is one of the Yummies--a pack of horrible, ferocious creatures with an appetite for sweets. What other choice do Guster, Zeke, and Mariah have than to run away from home to escape the mysterious beast?

On the run in a far corner of the world, Guster and his siblings discover a secret settlement known as the Delicious City. Now, with the Yummies hot on their trail and the Delicious City's Mayor determined to feed Guster to the beasts, Guster must embrace his talents as an Evertaster if he's going to save the city from collapsing and get his family out alive.