Detective Swifty, the adorable, clever swift fox, and his loyal, trustworthy prairie dog pal Gus solve yet another mystery right in their own Grassland town! The mystery takes Detective Swifty and Gus on an adventure through their local, Temperate Grasslands neighborhood as they help the local mailman, Mr. Whoopsies the whooping crane when the townsfolk's mail suddenly starts disappearing! This educational storybook introduces the reader to several endangered species of the Temperate Grasslands biome, but also provides interesting facts about each animal, place, or thing introduced in "Knowledge Boxes" that are scattered throughout the book!