Disease has altered the course of history since the first humans walked the earth. Pandemics have felled empires, decimated populations, and caused untold human suffering. It wasn't until Sir Alexander Fleming's discovery of penicillin in 1928 that scientists began to understand how to combat disease with antibiotics. This book looks at the scientists who paved the way for Fleming, the mechanics of antibiotics, and the looming challenges of antibiotic resistance today.