If you like your thrillers without the blood and gore that is often found in modern books, you will like Patricia Wentworth's Miss Silver books.
Miss Silver is an unlikely detective, but then so were Hercule Poirot and Miss Marple. Miss Silver started life as a governess and, by one of those fortunate coincidences that so often occur in books, one of her charges grew up to be something very high up in the police force. The Miss Silver books are set in, and just after, the second world war, in a world of rationing, housing shortages and making-do-and mending.
This particular book concerns the household of Ariadne, a retired actress, and her not very likeable family: the nephew who has expectations and is a little too friendly with some of the ladies in the district; his jealous wife, who has a lot to put up with, but who doesn't suffer in silence; the spiteful, grasping adopted daughter, and the old friend from theatrical days whose determination to be like Ariadne might be the death of her ..... Then there is the sluttish neighbour, whose son would undoubtedly have been in the care of Social Services, had she lived nowadays, and the up-and-coming actress who adores her small daughter, and brings in an old friend, Janet, to act as a surrogate nanny, just as Janet's ex fiance reappears.
When the first murder is committed, it is fairly clear that it was a case of mistaken identity, and that the intended victim was Ariadne. This means that almost everybody in the household had both motive and opportunity. Was the second murder another case of mistaken identity? I'm not telling, but I enjoyed the romp through this fairly light-hearted book, and I didn't guess "whodunnit" until just before the end.
I can recommend all of Patricia Wentworth's books. If you haven't read any of hers before, this wouldn't be a bad one to start with.