This man was accused of everything: quackery, witchcraft, fraud, espionage. One thing is indisputable: he had enormous knowledge in various fields of science, belonged to many secret societies and was at one time almost the main arbiter of the destinies of Europe, and not only it. His appearance in the middle of the 18th century in the secular salons of Vienna, Paris and St. Petersburg gave rise to the myth of the Count of Saint-Germain. Voltaire, in a letter to Frederick II, called him “a man who lives forever and knows everything.” Incredible rumors circulated about him everywhere: he was more than three thousand years old, he knew Jesus Christ himself, he could make diamonds and become invisible. Adherents of Saint Germain believe that he was a man endowed with supernatural abilities, the owner of the highest secrets and the elixir of immortality. Numerous detractors present him as a successful scoundrel, a third-rate alchemist, an impostor and a charlatan. Who was this man accepted by the sovereigns of France, Germany and Russia?