In the US 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 alternatives must be found. One alternative that is being considered by scientists is a kind of virus called a bacteriophage. "Phages"--viruses that kill bacteria but not humans--were discovered in 1915. Phage therapy was successfully used 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 behind the history of the phage, its discovery and development, as well as the strides that are being made to bring the therapy back to the West today.