Crime Fiction Sub-Genres – 3 Distinctions That Are Clear As Mud

by Kassandra Lamb ~ Genre definitions and crime fiction sub-genres can be quite murky and confusing for both writers and readers.

First there is the question of what is crime fiction. Some use it as a broader umbrella that includes any kind of fiction related to crime (including true crime, which isn’t fiction) and view mystery as one of its main sub-genres. Others use the two terms interchangeably (as we do here at misterio press).

If you do a search for mystery sub-genres, you will find lists of 4 sub-genres, or 8, or 10, or 12, or 15…or even 22. Some lists include thrillers, others view thrillers as a separate genre.

Also, one will find somewhat different definitions of these genres and sub-genres. And some stories have elements of more than one, so where do you put them?

Below are 3 distinctions between crime fiction sub-genres that can be pretty fuzzy. I will attempt to clarify, but I should note that these definitions are based on my understanding of the genre. Since there is so much confusion around these definitions, I hesitate to say that mine are definitive…but here’s my best shot.

Is it a Thriller or a Mystery?

Here is the clearest distinction I’ve ever heard (not mine originally, I learned it in a workshop at a writers’ conference):

  • In a mystery, something bad has already happened and the protagonist is trying to figure out who did the bad thing.
  • In a thriller, something bad is going to happen and the protagonist is trying to figure out how to stop it from happening.

Thrillers are usually fast-paced, but pacing, in and of itself, does not turn a mystery into a thriller. A very fast-paced mystery should probably be called “suspense.”

The only true thriller I’ve written, so far, complete with a ticking clock.

Thrillers often have higher, more global stakes, such as the destruction of the world, the assassination of an important leader, etc. But the stakes can be more narrow, such as a serial killer targeting a certain person and the protagonist must stop them before that person is killed. Or in the case of a psychological thriller, the stakes are often one person’s sanity.

In a thriller, the reader may very well learn early on the identity of the bad guy(s)/gal(s)… or is at least given insight into the antagonist(s), maybe even via scenes from their point of view. But this can happen in a mystery as well.

The key difference is the timing of the bad event (past or future) and the main goal of the protagonist (solve the crime or stop the bad event from happening).

But then there is the story where a bad thing happens and the protagonist is trying to solve that crime, and then another bad thing happens, and another…and it becomes apparent that even badder things are coming unless the protagonist can figure it all out pretty quick.

Sasscer Hill’s The Seahorse Trade shifts toward thriller when Nikki Latrelle suspects a missing girl has been taken by sex traffickers.

Is that a mystery or a thriller?

Good question. The answer is… it depends.

And that is when these other elements may swing the decision one way or the other.

If there’s been a murder, and then there are other murders, but they seem to be related to the first one—as in the killer is taking out people who might be able to incriminate him/her—and the stakes regarding the future bad thing are more narrow—as in someone near and dear to the protagonist is going to be the next victim—then it’s probably a mystery.

If a crime has happened and as the protagonist gathers clues and more crimes accumulate, it starts to look like a bad thing is going to happen that has much broader consequences, then it might very well be a thriller—especially if it’s fast-paced and the reader is given glimpses into the antagonist’s world.

Is it a Traditional Whodunit or a Cozy?

crime fiction sub-genres -- Book 1 in my traditional series
Book 1 in my traditional series.

Some people use these terms interchangeably, but my understanding of a traditional mystery is that it is similar to the more classic stories from the early years of crime fiction, ala Sherlock Holmes and Agatha Christie’s Murder on the Orient Express. (Some consider these stories a sub-genre in their own right, the Golden Age mysteries.)

Today, traditional and cozy mysteries both have amateur sleuths, and while gore, on-screen sex, and swearing are avoided in both, some of all of the above is allowed in traditional if it serves the story.

In cozies, those three things are pretty much forbidden, and usually the stories are set in a smaller community, such as a small town. Often the protagonist has a particular kind of vocation or avocation—bookstore owner, crafter, antiques dealer, etc. There are often animals involved as well.

Cozies also tend to be lighter, perhaps less complicated, stories than traditional or other kinds of mysteries.

But I can tell you, after having written a 10-book traditional series and now working on Book 11 in a cozy series, it can be really hard to tell where the line in between rests sometimes.

A sneak peek at the cover of my newest cozy!

Maybe that’s why I’ve decided that my next series will be a police procedural…LOL

Is it a Cozy or a Caper?

Capers are another lighthearted sub-genre, or at least they’re usually lighthearted. Some people even consider them a sub-genre of cozies.

But they aren’t always light and fluffy. The movie, Thelma and Louise comes to mind, which was lighthearted in places, but definitely not at the end.

The distinguishing characteristic of a caper is that it is written more from the criminals’ perspective. In the lighthearted ones, the bad guys/gals are often kind of inept, leading to humorous mishaps along the way. The TV show, Good Girls is a great example.

But there are plenty of other capers that focus on quite skillful criminals. They may very well have plenty of humor in them as well, but the mystery is in whether or not they will pull the crime off, and if so how.

There are also murky boundaries between some other crime fiction sub-genres, such as hardboiled detective stories and noir. But since I haven’t written in those sub-genres, I’m less clear about those distinctions. And then there’s cozy noir… 😉

Hmm, maybe I’ll get one of the other misterio press authors to write about them.

Readers, what crime fiction sub-genres do you like best and which ones do you feel have murky boundaries?

Writers, how do you decide where your stories fit?

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Posted by Kassandra Lamb. Kassandra is a retired psychotherapist turned mystery writer. She is the author of the Kate Huntington psychological mysteries, set in her native Maryland, and the Marcia Banks and Buddy cozy mysteries, set in Central Florida. She also writes romantic suspense under the pen name of Jessica Dale.

Misterio press produces an array of quality crime fiction. We post here twice a month, usually on Tuesdays, to alert you to new releases, to entertain, and to inform.

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  • Reply
    Barb Taub
    April 6, 2021 at 1:23 am

    Thanks so much for these clear definitions. As a reviewer, it constantly amazes me how many authors get their own book genres wrong.

    • Reply
      Kassandra Lamb
      April 6, 2021 at 12:38 pm

      Me too, Barb. But with those line-straddlers, it can be hard to decide.

  • Reply
    Lesley A Diehl
    April 10, 2021 at 11:25 am

    Thanks, Kass. I now understand what a caper is.

    • Reply
      Kassandra Lamb
      April 10, 2021 at 3:22 pm

      You’re welcome. Actually I just recently stumbled on that definition of a caper.

  • Reply
    M. E. Bakos
    April 10, 2021 at 9:44 pm

    Thank you for this post. Good explanations.

    • Reply
      Kassandra Lamb
      April 10, 2021 at 11:14 pm

      You’re welcome! Thanks for stopping by.

  • Reply
    Weekly News: 26th April 2021 - Author Help
    April 26, 2021 at 4:00 am

    […] distinctions between genres and sub-genres aren’t always clearly […]

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