Paul Hergenrother is a chemist who takes on huge, unsolved medical problems: antibiotic resistance, cancer, and neurodegenerative disease. His small-molecule compounds bind tightly to unconventional disease-related targets, deactivating them. For example, Hergenrother found compounds that eliminate plasmids, the DNA rings that deadly bacteria use to spread antibiotic resistance. That pioneering project led him to a general method for finding drugs that target a particular type of RNA -- messenger RNA -- as a way to silence disease-causing genes, something standard drugs cant do. Hergenrothers "ten-year vision" could lead to treatments for Alzheimers and Parkinsons.