"The Man Who Knew Too Much" is a collection of detective stories written by Gilbert Keith Chesterton in 1922. The stories revolve around the reclusive Horn Fischer, a man with the uncanny ability to solve crimes. While Chesterton's detective tales featuring Father Brown are well-known, the stories of Horn Fischer are equally captivating. In addition to the thrilling mysteries, these stories offer a glimpse into the author's thoughts on British history and the customs of the aristocratic class that governed the British Empire for centuries.