This is the first book in the series to not have organized crime as a plot element. Like all the other Campion books it is set an old family home with an upper-crust cast (Allingham comes near to breaking the fourth wall when she makes her police officer comment on the improbability of this given how few murders are actually committed in stately homes by rich families). In this case the dramatic personae are unusual primarily for their senescence: a tyrannical octogenarian widow keeps her elderly children and nephew living with her, under her thumb. They have no money of their own, no independent activities, not even any say as to their daily routines, food, clothing, etc. Even morning tea is forbidden simply because the dowager disapproves. They live according to the manner in which she conducted her home when she was a young wife in the 19th century. Julia, Kitty, Andrew, and William potter uselessly about the house, wiling away the empty hours by getting at each other. No wonder someone eventually snaps under these conditions! But who?
The one young person living at Socrates Close is Joyce, a niece by marriage who serves as companion, secretary, and general dogsbody, keeping the bills paid on time and trying to soothe her hysterical aunts. This was published in the 1930s and we are told that Joyce had a job which she quit to go live in this old house in Cambridge with these awful people she owed nothing to, which I didn't understand since she seemed a pleasant and capable woman, but I guess that's plot convenience for you. In any case, Joyce happens to be engaged to Marcus, a college friend of Campion's, and when one of her uncles goes missing he directs her to the detective, even though he thinks she is just being a sillyhead, you know how women are. I also didn't understand why Joyce was marrying Marcus. I hope it was for money, or he was good in bed or something, because his personality wasn't very enticing.
Aside from some minor antics early on, Campion cuts a more serious figure here than in earlier novels. I missed his crazy dialog but was not surprised, as he had been getting gradually more serious with each installment. At this point he is fairly sympathetic if a tad bland. I had previously read some books from later in the series, and am interested in seeing how her gets from this point to the rather bitter and unpleasant individual of a few years later.