However they called this mysterious number, which mathematicians denote by the letter φ: the golden ratio, the number of God, and the divine proportion. It plays a vital role both in the geometry of living nature and in human creations; it is used as the basis for works of painting, sculpture and architecture; moreover, adventure novels are dedicated to it! But is such fame deserved? What is true here and what is not entirely true, what is the history of the Golden Ratio in science and culture, and what caused such interest in a simple geometric relationship, the famous American astrophysicist and popularizer of science Mario Livio decided to find out. A fascinating investigation led to unexpected results... A fascinating plot and a non-trivial outcome, convincing logic and independence of judgment, little-known facts from the history of science and unexpected comparisons - this is what makes this popular science book a real detective story and an undoubted bestseller.