I’ve read this before, of course, and wasn’t there a movie? I had totally forgotten who the murderer was, though. While reading this, I was thinking of a different lots-of-people-dying movie… set in a castle or something? Where the first guy to “die” was the culprit. Hm… Yes! Murder By Death! Must be that one.
Anyway, this is pretty inspired. Christie writes in a brief preface that it took a long time to work out the logistics of this book, and you can see the sheer glee of having made it all work. And she gets to kill off ten miscreants in one book, and she doesn’t have to put in even a single sympathetic character.
And Then There Were None (1939) by Agatha Christie (buy used, 4.27 on Goodreads)