It's really a good thing I am not a detective. I was fairly sure that the obvious antagonist could not be the villain, simply because it seemed too easy: Christie was actively presenting him as the murderer, albeit a sympathetic murderer due to mental disturbance, one who didn't really know what he was doing, but she's never that obvious. It would have been an entirely new departure for her. (An interesting departure, no doubt, as Cust was so confused and so unwell that he was quite unlike her usual culprits.) And yet, suspecting that he was innocent, I had no idea who wasn't. I forgot, I'm ashamed to say, to suspect anyone else at all.

Instead, I was quietly marveling over the character work here. It seems to have taken a substantial step up from the Christie books I've read previously - from Hastings worrying about his thinning hair to Megan Barnard and her rather awful honesty... I was so impressed by it that I genuinely forgot to try and figure out whodunnit. That was a surprise. With Christie, it always is.