Saw this on Talking Pictures channel (UK - old films and TV) who are running all 4 of the original Maigret series (BBC, early 60s). It is another story involving a well-to-do family, which has some dark secrets they'd rather not have people know about -- a theme Simenon did several books on.
In this one the grandmother travels a long way to interrupt Maigret's holiday, and get him to come and investigate a mysterious death of a young girl. One of the sons-in-law - now running the family firm - was at school with Maigret (just a bit of a coincidence?!) and he had been a cheat and liar then, so Maigret is suitably intrigued.
The supporting cast are all excellent, between them must have racked up hundreds of appearances in assorted dramas and comedies. A nice comic turn is done by Dermot Kelly, an animal trainer at a circus, Maigret needs him to help control a fierce dog guarding a prisoner. Things begin to unravel in the family, as Maigret - with some fringe background info supplied by trusty Lucas - ferrets out the secret they're trying to conceal. And there's a dark ending, as one of the family decides to mete out suitable justice.
I enjoyed the episode, despite the couple of helpful coincidences which got the tale told in about an hour. And we never heard if Madame Maigret got her hubby back for the rest of her disturbed holiday?!