The history of an unnatural disaster-drug overdose-and the emergence of naloxone as a social and technological solution.For years, drug overdose was unmentionable in polite society. OD was understood to be something that took place in dark alleys-an ugly death awaiting social deviants-neither scientifically nor clinically interesting. But over the last several years, overdose prevention has become the unlikely object of a social movement, powered by the miracle drug naloxone. In OD, Nancy Campbell charts the emergence of naloxone as a technological fix for overdose and describes the remaking of overdose into an experience recognized as common, predictable, patterned-and, above all, preventable. Naloxone, which made resuscitation, rescue, and reversal after an overdose possible, became a tool for shifting law, policy, clinical medicine, and science toward harm reduction. Liberated from emergency room protocols and distributed in take-home kits to non-medical professionals, it also became a tool of empowerment. After recounting the prehistory of naloxone-the early treatment of OD as a problem of poisoning, the development of nalorphine (naloxone’s predecessor), the idea of reanimatology -Campbell describes how naloxone emerged as a tool of harm reduction. She reports on naloxone use in far-flung locations that include post-Thatcherite Britain, rural New Mexico, and cities and towns in Massachusetts. Drawing on interviews with approximately sixty advocates, drug users, former users, friends, families, witnesses, clinicians, and scientists-whom she calls the protagonists of her story-Campbell tells a story of saving lives amid the complex, difficult conditions of an unfolding unnatural disaster.