Bob Glass was a gifted thinker whose mind naturally belonged in no one box. Yet by the spring of 2006 he felt trapped. In the two years since its conception, his fifteen-year-old daughter’s science fair project had spun up into this grown-up model of disease control. He’d found data from the long-forgotten flu pandemic of 1957–58, estimated to have killed more than a hundred thousand Americans, and used it to test his model.