The excellent hapax has asked the following: Kit, how do you go about writing villains?

It's a really good question, to which I'm not sure I have an answer. Let me think about it.

To begin with, the stories I've written so far have tended to involve mysteries of one sort or another, which makes villains a slightly different proposition. If you're having a plot based on struggle between antagonists, you need a villain - or at least, one antagonist you'd rather see lose is common, though there are good works where you're really torn about what outcome you want. The first season of The Wire and Martin Scorsese's The Departed come to mind; in both of those, you know who ought to win - the guys on the side of the law - but you can see it from the criminal's side as well, so watching them be destroyed is not something you look forward to. Both of those, though, are basically procedural thrillers, in which the audience knows who's guilty at the outset; the tension lies in who will win rather than in whodunnit.

Mysteries depend for their tension on concealing things from the reader. There is a villain, sort of, but we don't know who he or she is, which makes it difficult for us to feel personal about taking them down. In essence, mysteries don't have a villain; they have a culprit. We see their malevolence entirely through the effect of their actions, and very little of them until the end - or at least, we see them, but don't realise they're the culprit if the writer has succeeded in their aims, so it's only at the end that the character is connected with all their bad actions. Till then, the villain is hiding in plain sight, and has to come off as a reasonable normal person. They can be unlikeable - it has to be plausible that such a person would do an awful thing - but if they cackle and rub their hands, you've given the game away.

As a result, villainy is something I use sparingly. My culprits tend to be people who've done something very bad, but I try to keep their scale of badness plausible. (Examples would involve spoilers, so I'll make this general.) Usually they think they're justified, or else want something enough to cut corners for it; the thing they want is generally desirable, so I can understand why they want it, but they're too willing to sacrifice other people to get it. Lashing out in panic is a plausible behaviour as well; in general, my idea of a villain is someone who makes a bad call for selfish reasons and then rationalises it to themselves rather than making amends. The reason for this is fairly simple: based on my experience and observations, that's generally the kind of person who causes a lot of harm in real life.

But then, I can have unlikeable or reprehensible people who aren't the villains as well. The heroine of my first book, Lola, stands by while people are beaten for information, picks fights out of touchiness, bends the law and generally speaking acts rather badly quite a lot of the time. The heroes of my second book have some very odd standards of behaviour; the entire plot of my third book, which I haven't finished yet and am just going to have to hope I can sell, revolves around the heroine making a decision many people would condemn. Morally flawed people are interesting to write about; so interesting, really, that I tend to spend more time on the faults of my heroes than my villains.

Beyond that, I don't really know. I come up with characters that seem appropriate to the situations and vice versa, but I don't have a particular plan...