[hobnail]

Am I the only one?

So many mysteries make the bad guy that's discovered at the end be one of the people the detective interacted with now and then during the story, but always a minor, insignificant character because we're not supposed to figure out who did it (e.g., the old "the butler did it" joke about mysteries). And at the end the author ends up doing all sorts of contortions and gymnastics to justify why that character did it.

I read one where it was a serial killer in London, nothing special about them or the victims so it could have been any of a million or so Londoners, but no, it had to be some guy the detective inspector chatted with once or twice.

I don't mind knowing up front who did it when it's a well written mystery and you get to watch the detective figure it out.