The book of the famous mathematician and promoter of mathematical science Ian Stewart is a collection of problems, puzzles and fascinating stories. The book's narrative is based on the adventures of the genius detective Hemlock Soames and his loyal friend, Dr. John Watsap. They are puzzled over solving problems with a mathematical background. The author pays attention to mathematical dates, riddles of prime numbers, theorems, statistics and many other interesting questions. This smart, fun book showcases the beauty of mathematics From the book, the reader learns about the shape of the orange peel, Euclidean doodles, pancake numbers, the square peg hypothesis, and other solved and unsolved problems. The book will be interesting to everyone who is not indifferent to riddles, loves mathematics and puzzle solving.