The Pale Horse has long been one of my favourites. It’s wonderfully macabre and atmospheric, and very, very clever.
The book even saved someone’s life, because a reader recognised the murder mechanism being used on a real person and contacted the police. In another case, an already-completed murder was discovered through the same symptoms.
If you’ve read Christie’s biographies and are aware of her wartime work in a pharmacy, you’ll enjoy extra resonance here. It also seems like Ariadne Oliver channels a lot of Christie’s own views here, perhaps even more so than usual.
The Pale Horse is also one of the books where I suspect Christie didn’t fully decide on the murderer until the end. As someone who writes murder mysteries myself, it’s surprising how easy it is to switch the murderer at the last minute. Partly because you have to lay red herrings throughout, so you can simply turn them into the actual crime.
I still feel I would have liked more revelations about the also-ran suspect (who wasn’t the murderer). Christie builds a lot of mystery around that person, but it doesn’t feel very resolved.
Here’s the Wikipedia page for those interested, but be warned that it does spoil the entire plot: https://en.wikipedia.org/wiki/The_Pal…
The 1996 Colin Buchanan film version is quite enjoyable but deviates significantly. I haven’t seen the more recent one, as the post-Hickson Marples have been generally dreadful (due to the scripts, not so much the actresses) and of course, Jane Marple isn’t even in the original text for this novel.
Like many Christie novels, this one is really calling out for a decent, accurate, generous-budget treatment. They don’t gain viewers or fans by needlessly altering plots.