One of the single greatest leaps forward in human healthcare happened because of an accident in a laboratory. This serendipitous event was the result of a summer vacation in Scotland and an unattended experiment. Dr. Alexander Fleming discovered penicillin, one of the first antibiotics, in 1928 when he noticed that mold had gotten into a petri dish and it had prevented bacteria from growing. This book explores Fleming's accidental discovery, the science behind antibiotics, and the dawn of the era of antibiotics.