Mundon Mandeville runs a thoroughly disliked repertoire theater company and is murdered inside a windowless room in the building although everyone involved has an alibi. 

Father Brown is a fictional Roman Catholic priest and amateur detective. He is featured in 53 short stories by English author G. K. Chesterton, published between 1910 and 1936.  Father Brown solves mysteries and crimes using his intuition and keen understanding of human nature. Chesterton loosely based him on the Rt Rev. Msgr John O'Connor (1870–1952), a parish priest in Bradford, who was involved in Chesterton's conversion to Catholicism in 1922.[ Since 2013, the character has been portrayed by Mark Williams in the ongoing BBC television series Father Brown.

Character

Father Brown on a case, illustrated by Sydney Seymour Lucas for The Innocence of Father Brown Father Brown is a short, plain Roman Catholic priest, with shapeless clothes, a large umbrella, and an uncanny insight into human behaviour. His unremarkable, seemingly naïve appearance hides an unexpectedly sharp intelligence and keen powers of observation. Brown uses his unimposing demeanour to his advantage when studying criminals, to whom he seems to pose no danger, making him a precursor, in some ways, to Agatha Christie's later detective character Miss Marple. His job as a priest allows him to blend into the background of a crime scene, as others can easily assume he is merely there on spiritual business. 

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