Friday October 13, 1307 went down in history as Black Friday. On that day, by order of King Philip IV the Fair, the leaders of the Templar Order were arrested, and hundreds of noble knights were taken under guard to Paris and other cities of the kingdom, where show trials of the Templars later took place. However, the king’s goal was not only to decapitate a powerful organization, but also to take possession of its untold riches. However, there was no wealth found either in the Temple in Paris, where the main residence of the order was located, or in the castles of prominent Templars. The order's treasury seemed to have sunk through the ground and has not yet been found. But what if the main missing treasure of the Templars was not gold and jewelry at all, but their knowledge? Perhaps the riddle of several centuries will be solved by the director of a small commercial company, Anna Berkutova, who mistakenly received an old casket with a secret... Previously, the book was published under the title “The Casket of the Count of Saint-Germain”