The Long Earth is a captivating space thriller mystery novel written by Terry Pratchett and Stephen Baxter. It is the first book in a series that explores a multitude of parallel Earths accessible through a device called the Stepper. The story follows Joshua Valiente, a man who possesses a unique ability to step between worlds, as he embarks on a journey of discovery and adventure. As Joshua explores the infinite possibilities of the Long Earth, he uncovers mysteries and encounters strange creatures. Pratchett and Baxter's collaboration creates a rich and imaginative world that combines elements of science fiction, mystery, and exploration.