Hard-Boiled to Cozy: Types of Mystery Novels

Learn the Difference

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Research the types of mystery novels to see where yours fits. Rosanne Olson / Getty Images

Mysteries for adult readers nearly all involve a murder — or (in the case of thrillers and suspense) at least the imminent threat of one. However, there's a wide range of sub-genres and other categorizing features in the mystery genre.

Do you aspire to be the next Agatha Christie and write a mystery novel? Authors who are pitching literary agents should understand where their manuscripts fit onto the (literary or virtual) mystery bookstore shelves.

First, do your research about the mystery genre in general. Then, read on to learn about the of the major types of mystery novels, below. Why?

Because hen you're writing a query letter for a mystery book to an agent, it helps to know where a bookseller will shelve it and to know the titles to compare it to. Within the major mystery book sub-genres of Hard-Boiled, Cozy, Procedural and Thriller / Suspense, there's a wide range of organizing features or sub-genres that booksellers use.

And, when you're trying to get books discovered online using SEO, metadata and optimized keywords or discovered on bricks and mortar store shelves, these categories and sub-genres are critical to helping mystery readers find your book.

Types of Mystery Novels

Hard-Boiled and Soft-Boiled

Hard-boiled mysteries and crime fiction generally feature a professional detective as the main character and the protagonists are often struggling with their own, estimable demons which haunt them as they solve the case.

Murder and crime happen in gritty settings and the violence is often graphically described.

Hard-boiled detectives harken from the noir days of Dashiell Hammett. Present day protagonists include Michael Connelly's Police Detective Harry Bosch, who works the current-day streets of Los Angeles, and James Lee Burke's Dave Robicheaux who plies his investigative trade on the Louisiana bayou.

A subset of detective fiction that is lighter in tone or with less explicit violence or sex is sometimes referred to as "soft-boiled," though this is less a less common term. An example would be Sara Paretsky's series featuring female P.I. V. I. Warshawski or Sue Grafton's "alphabet" series (A Is for Alibi, etc.), featuring Kinsey Millhone.

Cozy Mysteries or "Cozies"

What's cozy about these books is usually the setting. The murder takes place in an intimate environment, such as a small town, a neighborhood, or an all-girls private school. With the exception of the fact that somebody has been bumped off, the cozy tends to be light in tone; that is, it is crafted so as not to offend delicate sensibilities. So while the subject matter can include all manner of transgressionary behavior, the actual doings (such as murder, other violence, kinky sex, etc.) are not described in graphic detail.

The sleuth who solves the mystery is often an amateur, like Agatha Christie's elderly spinster Miss Marple or Karen MacInerney's stay-at-home mom, Margie Peterson. But not always — Alexander McCall Smith's No. 1 Ladies' Detective Agency protagonist Precious Ramotswe is a consummate professional.

Malice Domestic is an organization dedicated to the cozy genre.

Each year, the organization hosts an annual conference, produces an anthology and honors its best practitioners with Agatha, Lifetime Achievement and Poirot Awards.

Each year the Mystery Writers of America bestow the Mary Higgins Clark Award to what can generally be deemed a cozy (with a few other criteria).

Procedurals

A procedural mystery has as its key factor a blow-by-blow, thoroughly researched and specifically described analysis of how the crime is solved, by whatever means is the specialty of the main character. This may be authentically-researched detective legwork (as in a police procedural, such as in the novels of Joseph Wambaugh) or a scientific investigation of the evidence (such as in Patricia Cornwell's books featuring the medical examiner Kay Scarpetta or Kathy Reichs' series with forensic anthropologist Temperance Brennan).

Thrillers / Suspense

Thrillers and Suspense have different novelistic conventions than other mystery novels, but most booksellers shelve them in or near the Mystery area.

In a mystery novel, the protagonist's role is usually to find the killer. While his or her motive to solve the case may involve a personal element, physical threat to the protagonist generally towards the end of the story, as he/she gets close to solving the crime.

Thrillers and suspense novels, in contrast, start out with very high stakes for the protagonist. The plot may or may not involve a murder at the outset, but the threat of danger is palpable from the get-go, and the plot builds and twists from there.

  • In Thrillers — whether the stakes are personal (a man spots and pursues his father's killer years after the murder); patriotic (a bomb has been hidden somewhere in the White House), or international (a deadly virus will be released on a plane of 200 passengers heading from Hong Hong to Paris), the clock is ticking and the action and the pace are non-stop. An example is Alan Folsom's The Day After Tomorrow.
  • In Suspense — the protagonist is generally the one being pursued and must discover the whys and wherefores — again, upping the stakes from the beginning. But here the tension builds more subtly, often more psychologically — as in the novels of Patricia Highsmith, or in Gillian Flynn's Gone Girl.

Types of Mystery Novel Sub-Genres

Now that you've learned about the main types, learn about the sub-genres used to categorize mystery novels. 

  • Capers — Carl Hiaasen and Janet Evanovich are two authors who specialize in these novels that involve humor and / or humorous criminal escapades.
  • Classics — Include writers like Agatha Christie, Rex Stout, Raymond Chandler, Daphne du Maurier, Dashiell Hammett, Wilkie Collins, Edgar Allan Poe, and Sir Arthur Conan Doyle, and Patricia Highsmith.
  • Derivative — Some authors re-imagine historic or fictional characters as sleuths, often to appeal to existing fans of the author or period, as P. D. James did with Jane Austen's characters in Death Comes to Pemberley.
  • Domestic — Cats (Lillian Jackson Brown), dogs (Susan Conant), cooking (Diane Mott Davidson), knitting (Maggie Sefton), mommies (Liane Moriarty), tea (Laura Childs) … Home life is rich material, especially for cozies.
  • Investigator type — Official policeman, private investigator, nosy amateur, British — sometimes readers like to choose by type of sleuth.
  • Location-based — These mysteries are anchored in their environments and give a great sense of place along with the mystery. Examples include Craig Johnson's Longmire series set in Wyoming, Greg Iles often sets his books in his hometown of Natchez, Mississippi, Alexander McCall Smith's detective in Gaborone, the capital of Botswana, and Phoebe Atwood Taylor's Asey Mayo Cape Cod Mystery series.
  • Local interest — Also location-based, hyper-local mysteries are often set in beloved destination locales, doing double-duty as preview and / or souvenir of a trip or a "back home" reminder for people who've moved away. For example, Deb Baker's sleuth Gertie Johnson is a "Yooper" — from the Upper Peninsula of Michigan; Ellen Crosby writes wine country mysteries. Booksellers generally support local books (read how to approach booksellers to carry your local book, here).
  • Locked Room — These mysteries involve a crime that seems physically impossible – the name comes from a crime where the murder victim is in a room completely locked from the inside with seemingly no point of egress. Many authors (Sir Arthur Conan Doyle, Agatha Christie) have penned a locked room mystery or two, but writers who specialized in them include John Dickson Carr and Edward D. Hoch.
  • Historic — These are set in another era. For example, Elizabeth Peters Medieval series featuring  the monk Brother Cadfael, or her series set in 19th and early 20th Century Egypt with archeologist Amelia Peabody Emerson.
  • Sometimes mysteries will feature historic characters in major or minor roles, such as in Caleb Carr's The Alienist, set in New York at the time of that Teddy Roosevelt was police commissioner.
  • Multi-Cultural & Diverse — Mysteries that give readers a peek into diverse cultures communities are popular both within their own communities and as a window for readers into communities outside their own immediate circle. Examples are Grace Edwards' Mali Anderson novels set in Harlem and Tony Hillerman, whose books were involved Native American lands and issues.
  • Noir — Think dames with gams to kill for, Private Eyes who brood in trench coats, the reflection of neon strip joint signs reflecting in the windows. Gritty, dark, moody, the term fits the classics like Raymond Chandler and Dashiell Hammett, but also can be applied to modern-day works, like Walter Mosley's Easy Rawlins series.
  • Romantic Suspense —  A mash-up of romance and murder, one esteemed practitioner is Nora Roberts, who created the pseudonym J. D. Robb for writing in this sub-genre. Note that the Romance Writers of America bestow an annual RITA award in this category.
  • Sherlock Holmes — Some stores, like Mysterious Bookshop in New York City, dedicate a section to "Sherlockania" — original works, derivatives, scholarly studies, etc.
  • Supernatural / Paranormal / Fantasy — Many of these have mystery elements but, since the conventions of these genres tend to dominate, these books are generally shelved in those respective areas where fans can better find them.
  • True Crime — Before the Investigation ID Channel, we had to read non-fiction accounts of notorious murders. Truman Capote set the literary bar with In Cold Blood; Ann Rule is a long-time master of the genre.
  • Vocational — procedurals and thrillers often have protagonists with a special career or vocational arena, such as legal (by John Grisham and Scott Turow), forensic (Patricia Cornwell, Kathy Reichs), medical (Robin Cook), psychology (Jonathan Kellerman),  political (Vince Flynn), military (Tom Clancy), sports (Dick Francis).

Note that many (if not most) mystery novels contain elements of more than one sub-genre. For example, the South African Rennie Airth's protagonist Inspector John Madden is a World War I veteran and the mysteries take place in the early part of the 20th century. It can possibly be "shelved" (physically or virtually) in Historical or British Detectives or even International Crime.

And book publishing also follows trends and trends change. For example, imported and translated Scandinavian mysteries — around since Peter Hoeg's Smilla's Sense of Snow  — became wildly trendy after The Girl With the Dragon Tattoo by Stieg Larsson became a runaway bestseller. The popularity of any one genre may ebb and flow on the strength of the marketplace.