One hundred riders set out from New York state to run a race across the country. Among the riders is Robert Stroud, who is sure he will win on his horse Supreme. Also among the riders is Ethan Happ, who is mounted not on a horse, but on a mule. A novella-in-verse, Ballad of the Horse and Mule is a story of competition, steadfastness, and friendship. Written as a crossover book, Ballad of the Horse and Mule is for middle grades and also for adults.