The reason is that after years spent in the priesthood, Father Brown knows human nature and is not afraid of its dark side. Thus he understands criminal motivation and how to deal with it.

The stories included are "The Paradise of Thieves," "The Duel of Dr. Hirsch," "The Man in the Passage," "The Mistakes of the Machine," "The Head of the Caesar," "The Purple Wig," "The Perishing of the Pendragons," "The God of the Gongs," "The Salad of the Colonel Cray," "The Strange Crime of John Boulnois" and "The Fairy Tale of Father Brown."