We first meet him in “The Blue Cross,” a bumbling Essex curate, laden down with brown paper parcels and an umbrella. Chesterton borrowed the parcels, the umbrella, and perhaps the central character from his friend Father John O’Connor—once he had discovered, with surprise, that a priest (whom society assumes to be unworldly) must by profession be on close terms with the World and its sins. “The Blue Cross” illustrates this principle: Flambeau, the master thief, is out-thought every step of the way by the little priest, because the priest understands theft.

He had black clerical garb and a flat hat, sandy hair, and gray eyes as “empty as the North Sea.” He was Father Brown (possible initial J, possible first name Paul), one of the greatest colorless figures of detective fiction, who continued through another sixty-odd short stories; less concerned with hounding down criminals, relentlessly bringing them to justice, or with solving crimes, than with offering the offender a chance at forgiveness, or merely being the commonsense vehicle that illuminates a Chestertonian paradox. Other great fictional detectives receive biographies, as aficionados backfill details of their lives and exploits (where was Watson’s wound?); but Father Brown defies attempts to round out the details of his life outside of the canon. He had no home life, no early years, no last bow. He lacked color.

It was Chesterton himself who pointed out that his subtitle to the novel The Man Who Was Thursday, A Nightmare, tended to be overlooked. Perhaps that explains something else about the Father Brown stories: their logic is dream logic. The characters from a Father Brown story have little existence before the story starts, none after it has finished: each cast of innocents and malefactors is assembled to make the story work, and for no other reason. The tales are not exercises in deduction, for rarely is the reader presented with a set of clues and logical problems to work through. Instead they are the inspired magic tricks of a master showman, or tromp l’oeil paintings in which the application of a little brown suddenly turns an Eastern swami into a private secretary, or a suicide into a murder and back again.

The Father Brown stories are a game of masks—it is rare that an unmasking of some kind does not occur. The denouement tends less to be a summation of misdirected clues, than a revelation of who, in the story one has read, was really whom.

It has been said that Chesterton was not proud of Father Brown; it is true that he wrote the stories, especially in the latter days, to fund GK’s Weekly, the mouthpiece for his theories of Distributionism (a sort of bucolic socialism, in which every right-thinking Englishman would own his own cow, and a plot of land to graze it on). It is also true that many of the Father Brown stories are repetitive; there are only so many masks, so many times a man can disguise himself as himself. But even the worst of the stories contains something magical and rare: a sunset, perhaps, or a fabulous last line.