We were treated to a superb set – a Victorian living room, painted an authentic-looking rust red with pictures, china ornaments, bookshelves and pot plants. A fireplace to the left had a large portrait of the late Mrs Black and on the right were two windows to the garden. An archway at the back framed the bottom of the staircase. All this gave us the required impression of a rather oppressive country house from which at least some of the inhabitants were longing to escape. Full marks go to the set design, building and dressing teams.

The play, by William Dinner and William Moran, is perhaps not a great work of art, but it nevertheless works its magic and keeps its audience engaged using some time-honoured mechanisms: a mystery surrounding a death (was she poisoned? Yes, of course she was); a husband and a companion who are secret lovers; a maid who is obsessively loyal to her dead mistress; and a ready supply of arsenic from multiple sources. The focus is not about bringing in multiple characters with different reasons for us to suspect them, but instead it is on the two lovers and how the mystery pulls them apart. As each new piece of evidence emerges, it seems more and more likely that one of the two is the culprit and they go through cycles of loudly accusing each other and then backing down. By the end, however, they’ve gone too far and the truth, that the late Edwina had poisoned herself with the intention that the lovers would indeed be accused of her murder, is not enough to reconcile them.

As an aside, in the interval, the party I was with wanted to know who I thought had done it. I plumped for the maid (as did they) for no better reason than that she seemed the most unlikely. I might have gone for the policeman, though in my mind I couldn’t make that work. We were kept guessing until the end, though once it was over I was wondering why I didn’t work it out for myself sooner.

There are a few jokes in the script which were landed well. There are also some opportunities to get some extra laughs by playing it more as a farce, however the director, Maureen Davies, and her cast sensibly did not give in to this temptation, but kept it quite straight, preferring to make the characters and the plot believable and thus keep us interested in the outcome.

We were treated to a top-rate cast who all filled their roles to perfection.

The part of Gregory Black, the husband, a cool and rather uptight schoolteacher, was played by Stephen Deaville opposite Paula Hill as the slightly flighty companion Elizabeth Graham. These roles required them to range from being a loving couple through to doubt of, and anger with, each other and to exhibit various forms of suspicious behaviour. All this was handled with elegance and panache by both parties.

Ellen, the maid, was played by Amanda Sayers. She is fiercely protective of her former mistress and maintains her dominance over the rituals of the house, particularly over the permissible timings for the preparation of a cup of tea. This is a relatively small part from which a lot was made with a well-drawn, larger-than-life performance.

Last but not least, Neil Harrison gave us the policeman, Inspector Henry Martin. He came across as a seemingly benign presence with a practised way of needling out snippets of information from people while keeping his thoughts to himself. The audience, meanwhile, got enough to sniff out the red herrings and keep guessing, while remaining oblivious to the fact that they’re being played with by the author. This takes some subtlety, and it was executed here fantastically well.

While, as noted, the visuals were good, the sound design felt like a bit of a poor relation. Not much was required here, admittedly, but on the night that I was present there were some obvious glitches: the rain noise coming and going in an extreme fashion, and a distinctly mistimed door slam, which just sounded like a big stick being banged on the floor. More care here may pay dividends.

Another minor note was that it felt in places that the players weren’t quite on top of their lines. There were some points where characters started speaking together and then repeated themselves and there was the odd uncertain pause. This is perhaps forgivable as the parts are long, wordy and repetitive, particularly for the lovers, and the cast can certainly be commended for recovering well and staying in character.

Overall, this was a production that delivered on its promise – a knotty mystery to solve, a fun evening with a satisfying conclusion which didn’t ask too much of its audience, merely that they suspend disbelief and go with the flow.