In the U.S. alone some 90,000 people die from superbugs--bacteria that have grown immune to antibiotics. Officials agree that this problem will only get worse with time and new drugs must be found. One hope is bacteriophages, or "Phages"--viruses that kill bacteria but not humans. Discovered in 1915, phage therapy was successfully used against infections for twenty years before the invention of penicillin made them obsolete everywhere but Eastern Europe, where they are still in use today. In its first English translation, this book tells the fascinating story of the discovery and development of phages and details the strides being made to bring the therapy back to the West today.