Amateur sleuth and do-gooder Miss Marple (Margaret Rutherford) has been appointed to the board of a trust which recruits young offenders and rehabilitates them by posting them on a training vessel, her connection being that her grandfather was in the British Navy. When she arrives at the establishment's offices for her first meeting with the board, she allows a speech to be made, and gives a short one herself, but the man sitting next to her is anxious to get on for he claims to have something very important to say. Or he would if he had not taken a pinch of snuff and promptly keeled over dead...
Murder Ahoy was the final of the Miss Marple mysteries to star Rutherford, and by this time it's clear they were running out of steam as the formula was starting to grow stale. Perhaps if they had adapted an Agatha Christie original as they had done those previous three times they may have found more to say, but this one was only based on the famous character, and an new story was concocted for Dame Margaret to huff and puff her way through. But bearing that in mind, the appeal of seeing the actress in a part tailor made for her was not to be sniffed at - well, not worth taking a pinch of poisoned snuff for.
It's just that there was a definite air of been there, done that about Murder Ahoy which made it rely not so much on its mystery angle, and more on its personality. Fortunately, as usual with this series the cast was very well chosen, with the by now traditional foil to Marple in the shape of a venerable British character performer with just a touch of eccentricity himself filled out by Lionel Jeffries, always reliable in these situations. He played the Captain, Sydney Rhumstone, obviously not a suspect but treated as one for comic effect, and sparring verbally with Marple as she joins the training ship to carry out her own investigations.
She thinks that the murderer of that board member wished to silence him because he was about to speak out about some conspiracy or other, and in her home made lab she experiments on the snuff, which was stolen except for the patch she got on her glove, thereby working out that strychnine was the poison used. Here we see her extensive crime library, a wall of mysteries and thrillers which she consults, and have evidently come in very handy over the years; the book she finds her solution in happens to be part of the ship's library too, another reason for her suspicions to be raised. But she has competition: not from the murderer, but from the longsuffering Inspector Craddock (Charles 'Bud' Tingwell).
So there are a few familiar faces here, and not only because of the recognition factor of the cast, as the movie Marple's loyal companion Mr Stringer was back as well, played by Stringer Davis who just happened to be Rutherford's loyal companion in real life. She insisted on his presence in many of her movies, so there he was. It's details like this that made the series cosy and continues to attract fans to this day, but much of the appeal rests on Rutherford's shoulders, as we like to think she was essentially the way she was in reality as she was in the Marple role. She certainly prompts a good few chuckles, whether it was asking the Inspector if he was suggesting she was unhinged to her announcement in the action-packed finale that she had been the Ladies National Fencing Champion in 1931. What a pity that too much of Murder Ahoy was coasting along on her charm, and that so little was actually happening in the plot. Music by Ron Goodwin, famous theme present and correct.