This week I focused on MHO of what makes a good mystery: believability, the right sleuth, etc. Today I'll finish with the end, that final wrapping-up that either leaves the reader satisfied and wanting the next book from the author or...else.
Golden Age mysteries tended to have a rather lengthy scene where the sleuth replayed the whole scenario, pointing out clues and often ending with a dramatic accusation: "And that's how I deduced that (bum-bum-bum-bahhhh) the butler did it!"
Possibly because television doesn't adapt well to that, we tend to end pretty close to the climax these days, the denouement brief and often spattered with pithy humor as the characters settle back into their normal routine.
It's hard to strike the right balance: too much explanation at the end or leave the reader unsure of what happened and why? I've read books by well-known, well-paid authors where there needed to be at least one more chapter; it felt like someone had taken an ax and chopped the story off. I've also read books where all the explanation in the world didn't make me believe that ending was probable, even possible.
Here's one writer's confession: I don't like writing the last chapter. Though I know there has to be a life-and-death struggle at some point, I don't like trying to capture it in words, and it isn't part of the attraction of mystery for me. When I watch movies or TV shows, I often leave the room once the killer's identity is revealed. I don't care for the final chase scene, the "book 'em, Dano" moment.
When I write, I make myself do it right, paying as much attention to the end as to the rest, but for me, the fun part is building up to it: planting clues, establishing character, following the sleuths' line of thought. I'll write that final chapter, and I'll do it as well as I can, but once we all know whodunit, I'd just as soon move on to the next novel.