The invention of double-cross hybrid corn is celebrated as a major scientific achievement that quadrupled yields and launched modern industrial agriculture. Yet, its adoption was championed as the solution to the 1920s farm crisis, a crisis caused not by low yields, but by overproduction amid collapsing farm prices. The Double Cross resolves this paradox by demonstrating how the hybrid corn revolution and parallel efforts at rural social engineering were co-developed responses to the perceived failure of American farms and farmers. The botanists and geneticists responsible for hybrid corn—including George Shull and Charles Davenport—were also prominent eugenicists who sought to apply principles of heredity to improve both crops and people. This project is the first study centering this intersection, revealing how scientific progress and social control fundamentally reshaped rural America.