The police find a man dressed as a priest with his hands in a safe. They arrest him but he turns out to be Father Brown (Alec Guinness) who was returning the money stolen by a parishioner. The church is sending the Holy Cross of Saint Augustine to the Eucharistic Congress in Rome. The police tell them that elusive thief Flambeau is after the priceless artifact like the many treasures he has stolen in the last 10 years. Nobody knows what the master of disguise actually looks like. Father Brown determines that the police would be easy targets for Flambeau and transports the Cross himself. Eventually he is alone with Flambeau as intended and he tries to reform him. Flambeau refuses and escapes with the Cross. Despite the disappointment, he tries to entice Flambeau again with the help of Lady Warren.Alec Guinness is great as Father Brown. It's a great character and Guinness is magnificent playing him. It's a fun mystery for awhile until Flambeau is revealed. Then it repeats again and again for Father Brown. It's fun to watch him in a caper to catch Flambeau. It's less fun to watch him try to convert Flambeau. Guinness always tries to keep his character light and fun.

It's odd that "gently comic" (as another reviewer put in) usually means "quite unfunny". Or rather, it means "we laugh at a harmless, good character". This film could have done with trying less hard to make us laugh. I can't stand seasickness jokes (tho I rather liked Flambeau's line when disguised as a priest "I must partake of the suffering of others"). And the bit where Brown and the librarian keep dropping/stepping on spectacles - I watched it stone-faced. Brown is quite bumbling enough without being "blind as a bat without my glasses" as well. The film opens well with Brown apparently robbing a safe (of course he's putting the money back). Sid James and Cecil Parker give sterling support, and the friendship between Brown and Lady Warren is touching, and I love the garage man who whisks the priest into the dance. This could have been a good film. Occasionally Guinness becomes entirely serious about saving Flambeau's soul and we glimpse what it might have been. It's based on the first Father Brown story in which Flambeau appears, and some of the plot is retained - the chase across town/country, the swapping of parcels, the wrestling holds, the man who's unmasked because he gives the wrong answer about... in the original story it's sin, not drive shafts. Read the story, it's one of the best (also read the one about the silver forks and the extra waiter). And it whisks you through a wild vision of Victorian London (Camden Town is as benighted as Darkest Africa, and they end up on Hampstead Heath - standing in for the high place where the Devil tempted Christ).

I'm old enough to have seen this film on its release in the cinemas, and, whilst it's not easy to think of a film these days being a success unless millions have been spent on it, this film hung on two superlative performances from Alec Guinness and Peter Finch and the screenplay was worth two of anything you'd hear today. So why, I ask, has it not been released on DVD for a new generation to enjoy? Is it thought too dated? Not exciting enough? Too cerebral? Not a bit of it. It's a thoroughly enjoyable film with moments of high tension and a supporting cast rich in character (including Bernard Lee who was the first M in the Bond films)

1st watched 10/26/1997 - 8 out of 10(Dir-Robert Hamer): Guiness provides a delightful portrayal of a whimsical Father Brown who plays detective on the side. Despite slow spots in the story, the portrayal and determination of Father Brown to get his man soul and all keeps us watching.