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Mystery/Thriller

What Makes a Good Mystery Series?

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Clare Barnett

Staff Writer

Clare Barnett lives in Richmond, Virginia, with her husband and daughter. She delves into all genres but has a soft spot for fantasy, mystery, and memoir. When she’s not working her way through her to-read list, she’s reading and writing about bookish things. Twitter: @clarebar. Inquiries: clarerbarnett@gmail.com.

When I find a new, exciting mystery series, I know it’s time to clear space on my bookshelf. Like many mystery fans, when a new sleuth wins me over, I want to read every book they’re in. So what is it about a good mystery series that makes readers like me commit for multiple novels, dozens of murders, and thousands of pages? The answer lies in the series’ comforting blend of familiarity and intrigue. With a favorite series, I get to spend time with my favorite detectives and a cast of familiar faces, from police chiefs to neighborhood busybodies. Whether cozy or hard boiled crime, the best series give readers a chance to step into a familiar world that still offers guaranteed twists and turns with every crime. Here are the key elements of mystery series that keep readers hooked, book after book.

An Original Sleuth You Can Root For

A mystery series is only as good as its sleuth. Sometimes, it’s one with incredible powers of observation, like the Sherlockian IQ in Joe Ide’s IQ series. Sometimes they can talk to ghosts like Alexa Gordon’s Gethsemane Brown. Whatever their crime-solving talent, the central character has to be compelling. Sometimes they’re dark and brooding, like Jo Nebso’s Harry Hole or dapper and fastidious like Agatha Christie’s Hercule Poirot. Whether a hard-drinking Texas Ranger like Darren Matthews in Attica Locke’s Highway 59 series, or sarcastic amateur detective and socialite like like Lady Georgie in the Her Royal Spyness series by Rhys Bowen, the series’ main sleuth is usually noble in their own way, putting themselves in danger book after book to restore justice. Once the sleuth gets us on their side, we’ll be clamoring for their next case. 

A Loveable Sidekick

Every Sherlock needs their Watson. Whatever the sleuth’s strongest qualities, the sidekick is usually their opposite. Whether the sidekick is a junior colleague, loyal friend, or grand mage, their relationship with the main character provides an entertaining foil for the sleuth’s problem-solving. Sherlock’s Watson and Poirot’s Captain Hastings are iconic and somewhat bumbling. Others like Walter Mosley’s Mouse in the Easy Rawlins series or Ranger in Janet Evanovich’s Stephanie Plum series are helpful but also dangerous. Often, you can count on sidekicks to deliver the killer one-liners. Personally, I always fall for some solid crime-fighting banter. 

Setting as Character

In great novels, the physical setting is a character in itself. In a great mystery series, it’s the foundation of the world that the reader wants to return to again and again. For example, Ely Griffith gives us contemporary English beaches in The Brighton Mysteries, while Walter Mosley brings 1948 Los Angeles to life through the adventures of Easy Rawlins. Sometimes, the setting comes with a supernatural twist, like the fantastical modern London in the Rivers of London series by Ben Aaronovitch. Each mystery offers a chance to explore a new corner of a setting that, depending on the series, can seem deceptively safe or teeming with danger. Each investigation explores unique aspects of the geography, social life and values of the novel’s time and place.   

Slow-Drip Personal Life

In murder mystery series, the hardest puzzles to solve usually stem from personal dilemmas rather than corpses. In a satisfying whodunnit, our sleuth usually nabs the killer within 300 pages. Asking the cute coroner out, however? That’s at least three books worth of indecision. Once an author draws us in with a compelling sleuth, they know we’ll sit patiently through a few books (or a dozen) to see if characters like Sookie Stackouse in Charlaine Harris’s The Southern Vampire Mysteries work out their romantic dilemmas. Personal growth in mystery series is often on the back burner, but authors give us intriguing threads of relationships, families and ambitions that have nothing to do with murder. While our detective found the real killer, we’ll have to wait for the next book to find out what happens in their personal life.


An endearing sleuth with a loveable sidekick solving murders and occasionally their own personal issues in a vivid setting is a recipe for a successful mystery series. If you want suggestions for your next favorite mystery, check out our list of the 25 of the Best Murder Mystery Books.