Billy and the Minpins is a children's book by Roald Dahl, originally published as The Minpins. It tells the story of Billy, a young boy who embarks on an adventure into a mysterious forest despite his mother’s warnings. The forest is filled with dangerous creatures, including the fearsome Gruncher, a dragon-like beast that can run as fast as the wind.

Billy soon encounters the Minpins, tiny people who live in the trees and ride on birds. They are constantly in fear of the Gruncher. The Minpins live in intricate treehouses connected by rope ladders and bridges, hidden from the dangerous world below. With the help of the Minpins, Billy devises a plan to defeat the Gruncher and return home safely.

The story captures Dahl's signature blend of imagination, adventure, and wonder, with themes of bravery, curiosity, and resourcefulness. The Minpins themselves are portrayed as peaceful, clever, and kind, and their world is filled with whimsy and magic.