"The Cat Among The Pigeons" is a book with a sprawling plot and a mostly transparent plot that is rescued and made quite entertaining by a cast of, to use Christie's term, "most unusual" women.
Although it is the thirty-fourth Poirot book, Poirot doesn't appear until the last third of the book and his role is mostly confined to that of expository device (one of the last chapters is even called "Poirot Explains"). He offers some insights and uses his connections to get information and assistance, but this is a book that he's in rather than a book that is about him.
The story is not a typical whodunnit, with a narrow focus on an evil deed and the use of Poirot's little grey cells gradually to eliminate a long list of interesting suspects.
It's a story of... well it's complicated. It's about a revolution in a Middle-Eastern Kingdom, espionage, jewel smuggling, abduction and murder. murder, abduction, and jewel smuggling. It's not the tightest plot but the sprawl is contained by using the first term of the academic year at a Meadowbank, a prestigious and slightly unconventional private school for girls to bring all the crucible that melds these different elements together.
I think the book is best enjoyed by approaching it as if it were not a Poirot book. This was published in 1959, by which time Christie seems to have become rather bored with Poirot. It seems to me that, in "Cat Among The Pigeons" she leverages the Poirot Franchise to produce what is almost a spin-off book in which she responds to the mood of the times by spinning a tale of international espionage (this was the year when "Goldfinger" the seventh Bond book, was a best-seller) and by reflecting on the changing role of women in post-war Britain.
The book is dominated by strong, resourceful women who are behaving in ways that they take for granted but which the men in the story (mostly Establishment types) see as "most unusual".
The most notable of these is Miss Bulstrode, the founder and headmistress of Meadowbank school. I really liked Christie's portrait of a charismatic, visionary woman who has the political nouse and Establishment influence to get things done, is passionate about education, sees change as the only constant and is genuinely interested in the girls in her care and the staff in her charge. Miss Bulstrode is redoubtable but she's not an alpha male in a frock. She's insightful, listens well, keeps an open mind, accepts risks and takes responsibility for her decisions. She's also often quietly witty.
In addition to Miss Bulstrode, we have a mother and school-age daughter pair where the mother worked in Intelligence during the War and is now comfortable setting off alone by local bus across Anatolia and daughter is astute enough to figure out the mystery and resolute enough to act independently to fix the problem.
We have a fearless, no-nonsense (and completely tactless) Games Mistress, a bright but socially inept mathematician, an extremely efficient and independent secretary, and a young teacher who is too bright and too passionate for most of the people around her to see her as anything but "slightly touched". In the final chapter, we have one more woman who takes decisions that speak to strength of character and clarity of purpose, who is again described as a "most unusual woman".
Perhaps the most tiresome part of the book was the part with Poirot in it. His late involvement resulted in a great deal of repetition. His grandstanding in the get-everyone-in-one-room-and-shout-j'accuse scene rang rather hollow and the actions it triggered were the least plausible part of the plot.
I also got rather tired of having the phrase "Cat among the pigeons" repeated and repeatedly explained. It and the phrase "new lamps for old" could have been turned into an intoxicating drinking game.
This isn't one of Christie's strongest mysteries but I think that, if you take it on its own terms, it's a very entertaining novel.
I listened to the audiobook version which was expertly narrated by Hugh Fraser. Click on the SoundCloud link below to hear the opening of the book,