I think it was Lin Wewei who came up with the idea. “The best way to find The Top 20 of Agatha Christie’s books is by asking the well read GAD members to list down theirs. What is your Top 20?” Some of us set to work on it. If I’m right 20 GAD members sent in their suggestions. The results were:
Books that were not even mentioned once (8):
1. Parker Pyne Investigates, 1934 (Parker Pyne)
2. They Do It with Mirrors, 1952 (Miss Marple #5)
3. Dead Man’s Folly, 1956 (Hercule Poirot #27)
4. The Clocks, 1963 (Hercule Poirot #29)
5. Third Girl, 1966 (Hercule Poirot #30)
6. Passenger to Frankfurt (1970)
7. Elephants Can Remember, 1972 (Hercule Poirot #32)
8. Postern of Fate, 1973 (Tommy & Tuppence Mysteries #4)
Most Recommended books (21):
1.- 2. TIE The Murder of Roger Ackroyd and And Then There Were None (17/20)
3.- 4. TIE A Murder is Announced and Towards Zero (16/20)
5.- 8. TIE Death on the Nile; Murder on the Orient Express; Five Little Pigs; and After the Funeral (15/20)
9.- 10. TIE The Body in the Library and Crooked House (14/20)
11.- 13. TIE Evil Under the Sun; The ABC Murders; The Moving Finger; (13/20)
14.- 15. TIE The Hollow; and The Pale Horse (11/20)
16.- 17. TIE Cards on the Table; and Mrs McGinty’s Dead (10/20)
18. Hercule Poirot’s Christmas (10/20)
19.- 21. TIE Peril at End House; Murder is Easy; and Ordeal by Innocence (8/20)
A couple of notes:
- I’ve not taken into account the short story collections
- I used a chronological order. No instructions were given and some participants only said “in no particular order”.
It’s of interest to compare this list with the one compile by Curtis Evans at The Passing Tramp some six years ago, The Results: Favorite Agatha Christie Novels:
1. And Then There Were None (24)
2. Murder on the Orient Express (23)
3. Death on the Nile (21)
4. The Murder of Roger Ackroyd (18)
5. Five Little Pigs (15)
6. A Murder Is Announced (14)
7.-8. TIE Evil under the Sun and The Hollow (10)
9. Curtain (9)
10.-11. Crooked House and The Moving Finger (8)
The next 9, making the top 20, are as follows:
12.-14. TIE The ABC Murders, The Body in the Library and Endless Night (7)
15.-18. TIE After the Funeral, Cards on the Table, 4.50 from Paddington and Hercule Poirot’s Christmas (6)
19.-20. TIE The Murder at the Vicarage and The Mysterious Affair at Styles (5)
Thanks for joining in, it was great fun. My apologies for any mistake. Your comments are welcome.
A Crime is Afoot 
Interesting that so many of the “not mentioned once” books come from the tail-end of her career. I’d agree that these are are her weakest and have always felt some of them shouldn’t have been published, though I do have a fondness for Postern of Fate purely because it’s the last of the Tommy and Tuppence books.