It started as a search for heroes. It became a hunt for the most elusive equestrian charlatan of all time. If Frank Hopkins is to be believed, he led one of the most exciting, challenging and colorful (albeit unrecorded) lives in the late nineteenth century. No one rode more miles, eluded more danger, or befriended more famous people than he did. During the 1930s and 40s the self-proclaimed legend told a naive American public that he had won nearly five hundred endurance races, including an imaginary race across Arabia on a mythical mustang named "Hidalgo." Hopkins' remarkable career...