On a cold day in 1667, a renegade physician named Jean Denis transfused calf’s blood into one of Paris’s most notorious madmen. In doing so, Denis angered not only the elite scientists who had hoped to perform the first animal-to-human transfusions themselves, but also a host of powerful conservatives who believed that the doctor was toying with forces of nature. Just days after the experiment, the madman was dead, and Denis was framed for murder. “In an era when science and superstition were barely distinguishable, blood transfusion became embroiled in contentious religious and ethical debates, served as a vehicle for political intrigue, and even drove men to murder,” writes Tucker, associate professor at Vanderbilt University where she specializes in the history of medicine. Amid this atmosphere of uncertainty, transfusionists like Denis became embroiled in the hottest cultural debates and fiercest political rivalries of their day. Taking readers from the highest ranks of society to the lowest, from dissection rooms in palaces to the filth-clogged streets of Paris, Blood Work sheds light on an era that wrestled with the same questions about morality and experimentation that haunt medical science to this day.