Except the characters and the fact that it is a detective story, this movie has not much to do with the original father Brown. In fact this is a very German movie which is slightly based on Father Brown stories
If you see this film without regard of the period/place it was made, you might find the storyline and acting terrible backdated. However: this movie fits perfectly in the German 60's era of somewhat fuzzy detective "thrillers" after stories of Edgar Alan Poe and other English writers. For that era I find "Das schwarze Schaf" and also the second father brown movie "Er kann's nicht lassen" better than average.
The feeling of those movies (and especially the both Father Brown films) rely very much on the big-band jazz sound of Martin Boettcher, who was regularly asked to compose soundtracks during that period (later, Boettcher would compose the famous Winnetou soundtracks).
As conclusion: Do not watch this movie if you want to see the Father Brown of the stories. Do not watch it if you hate backdated films. For all others it is an old but nice movie, typically for it's era.
