The rash act almost led to a new epidemic of one of the most terrible diseases this world has known - the bubonic plague. The ominous bacterium had been waiting in the wings for many centuries - and it did. Extracted from the ground, it mutates and is ready to begin a new march across the Earth. But in the fourteenth century, this threat was already hanging over the world. The plague spared neither the poor nor the nobility. To protect the royal family, philosopher, alchemist and healer Alejandro Sanchez arrives at the court of the English monarch Edward III. His path was not at all strewn with roses, and only thanks to a random coincidence of circumstances (or the will of Providence) he manages to find a cure for a fatal illness. Sanchez entrusted his secret to his secret diary, which will be passed down from generation to generation in a family of healers and six centuries later again will save the world, as predicted.