I am not quite sure what to say about this book. Adam Penhallow, the man who will eventually become the victim, like Simeon Lee from Hercule Poirot's Christmas, is utterly loathesome. He is the classic early twentieth century affluent male demanding that all of his relatives dance attendance upon him as they wait for him to die.
Heyer does a bang-up job sketching out all of the various characters, from Faith, Penhallow's long-suffering, mild second wife, mother to Cliff, to all of his children. Of them, only one, Char, has really managed to break free of her family, and that is because she inherited a legacy from a grandmother that has made her independent. Penhallow has seven sons, Ray, Jimmy the Bastard, Bart, Con, Eustace (or something like that), Aubrey and Cliff, who is the only son by Faith. He has decided that he wants all of his children at home, in his not-waning-nearly-quickly-enough years, so that he can psychologically torture them and hang their impoverishment over their heads, as he controls all of the money. I'm pretty sure there's another random daughter, but I don't remember her name. There is at least one daughter-in-law, who bitterly hates Penhallow.
It is only a matter of time before one of them breaks. One of them breaks.
One of the marvelous things about modern economies is that all of those children would have at least had the option of telling him to go fuck himself and set out to make their own way in the world without regard to the inherited wealth. He really needed to go fuck himself.
The murder doesn't occur until late in the book, approximately 64%, and it is no surprise, because we are in on the details. The only real mystery is whether or not the police will actually figure it out.
I read this one for the Country House Murder square.