Simon Forman (1552-1611) is one of London's most infamous astrologers. He stood apart from the medical elite because he was not formally educated and because he represented, and boldly asserted, medical ideas that were antithetical to those held by most learned physicians. He survived the plague, was consulted thousands of times a year for medical and other questions, distilled strong waters made from beer, herbs, and sometimes chemical ingredients, pursed the philosopher's stone in experiments and ancient texts, and when he was fortunate spoke with angels. He wrote compulsively, documenting his life and protesting his expertise in thousands of pages of notes and treatises. This highly readable book provides the first full account of Forman's papers, makes sense of his notorious reputation, and vividly recovers the world of medicine and magic in Elizabethan London.