Aaron the Aardvark meets a green worm-monster named Grizible. They become friends.

When Aaron sees some thieves hiding loot in the sewers, he follows them -- and the thieves chase Aaron.

Grizible and his family trick the thieves, make them leave the sewer, and save Aaron.

This is a read-aloud book with poetry, word-play, and treats for the child and adult reader. Definitions expand the child's vocabulary.

Hannah Tuohy continues as the illustrator of this, the third in the Aaron the Aardvark series.