In 1872, the Qing Empire sent 120 boys to America in the hope that they would unlock the mysteries of Western innovation. They studied at New England's finest schools, befriended luminaries such as Mark Twain and Ulysses S. Grant, and exchanged ideas with their American peers that would change the course of both nations. But when anti-Chinese fervor forced them back home, the young men faced a new set of obstacles, having to overcome a suspicious...