I found this utterly charming film by accident - it was the bonus feature of the box set (Region 1) of the later series "The Last Detective" with Peter Davison, also based on the work of Leslie Thomas, but made two decades later. The story of the Bernard Cribbens film is based on the same one told in the Peter Davison series pilot; comparison of the two versions is interesting, and although the later TV series was good, this Bernard Cribbens film is simply wonderful. Davis is a determined plodder but the action never ever seems slow - from one clue to the next, the charming vignettes and excellent acting move the story along perfectly. The action here follows the Leslie Thomas book closely and much of the dialogue is taken verbatim from the novel. I have watched it a few times, finding new things to appreciate with each reviewing - it's funny, touching, AND an excellent detective story - AND has great performances by Bernard Cribbens and the rest of the cast.
Altogether, a treat!
Altogether, a treat!