In the fourteenth century, the bubonic plague raged in Europe, sparing neither kings nor beggars. But even then there was a means to protect against it. Alejandro Sanchez and his adopted daughter remained the only keepers of the secret, but they are forced to wander around Europe, hiding from numerous ill-wishers. During these wanderings, the manuscript of an ancient alchemist accidentally falls into the hands of a healer. An accurate translation could save thousands of lives. But what will happen if it falls into the wrong hands? And many centuries later, at the beginning of the third millennium, the world is facing a new epidemic. Dr. Janey Crowe, doing independent research at her own risk, discovers a priceless manuscript. But Alejandro did not have time to finish the translation...