Halloween is creeping right up on us. Is your costume still a big question mark? All the answers lie within your favorite mystery novels. I put on my houndstooth deerstalker cap, took a few puffs on my pipe, and used my powers of observation and deduction to come up with mystery-themed costumes that could kill at any Halloween party. And since they’re all pretty easy to pull together, you can prep your costume and still have time to get to the twist ending in your current mystery read.

I myself am a passionate Halloween person. I put a lot of time and effort into my costume each year. So, of course, I’ve already got my costume carefully crafted and ready to go, right? …right? Okay, no. I don’t. I’m currently freaking out because I haven’t landed on the perfect concept. But coming up with costume ideas for other people is always more fun than figuring out my own. So enjoy the fruit of my creative labors!

Get 15% off annual All Access memberships for a limited time in celebration of Book Riot’s 15th anniversary! Savings amount to more than 3 months of free unlimited access to our entire content archive, plus features like Collections and the New Release Index. Claim your savings and start leveling up your reading life.

If you love gritty police procedurals like In the Woods by Tana French, you should dress as…

A Chalk Outline of a Murder Victim

Countless mysteries begin at a crime scene with the chalk outline of a dead body on a back alley sidewalk and a detective arriving, coffee cup in hand, to get briefed on the grisly murder. Take your inspiration from that opening scene by dressing as the chalk outline. Wear all gray. Paint your face too, if you want to go all-in. Wrap a string of white ribbon or tape around the edges of yourself, from head to toe. Accessorize with yellow caution tape, numbered evidence markers, and a splash of blood. Then strike a pose like a dead body splattered on the sidewalk. Make it a couple’s costume by dressing your partner like a jaded detective with a checkered past.

If you love classic whodunits like Agatha Christie’s And Then There Were None, you should dress as…

Clue (aka Cluedo)

Has it been done before? Sure. Both the board game and the 1985 film have inspired Halloween costumes for decades. But it’s perennially popular, especially if it’s done well. The cast of suspects makes for an excellent group costume. But if you can’t convince five friends to join you as Colonel Mustard, Professor Plum, Miss Scarlet, et al., get creative for a solo costume. Wear a monocle, a fake mustache, and a bloody dressing gown and be the murder victim, the enigmatic businessman Mr. Boddy. Or dress as Clue’s forensic scientist by wearing a lab coat with a Clue Laboratories badge and carrying a candlestick, a lead pipe, a wrench, and a rope in plastic evidence bags.

If you love cozy mysteries like Arsenic and Adobo by Mia Manansala, you should dress as…

A Cozy Mystery

Thanks to hit shows and movies like Only Murders in the Building, Knives Out, and The Thursday Murder Club, cozy mysteries have hit the mainstream. Turn the popular subgenre into a costume by wearing your coziest outfit (chunky knit shawl, pajama pants, and bunny slippers) and carrying the tools of any good amateur detective (magnifying glass, spiral-bound notebook, and wooden pipe). Side bonus, you’ll be extremely comfortable for all of Halloween night.

If you love true crime and true crime-y fiction like Tasha Coryell’s Love Letters to a Serial Killer, you should dress as…

A True Crime Podcast Host

True crime is a wildly popular segment of the podcast world — so popular that it’s started to circle back and influence mystery novels, movies, and TV shows. Dress as a true crime podcast host by wearing headphones, carrying a microphone and an armful of redacted documents, and wearing a shirt that says, “The husband did it.” Commit to the bit all night by narrating your friends’ every move in a smooth podcast narrator voice and throwing in unsettling statements like, “Little did he know that was the last time he’d see the victim alive.”

If you love thrilling heist novels like S.A. Cosby’s Blacktop Wasteland, you should dress as…

A Cat Burglar

Nothing thrills like a good heist. And who doesn’t want to be the crafty acrobatic bandit who sneaks in and steals the million-dollar diamond? Turn a classic heist character into a pun by dressing as a cat burglar in a black-and-white striped shirt, a black mask over your eyes, black gloves, black cat ears, whiskers, and tail. It’s cute, and it gives you permission to sneak up on kids and steal their candy. It’s part of the role!

We hope you enjoyed these Halloween costume ideas based on your favorite mystery novels! Get more bookish costume ideas below:

The Best Bookish Halloween Costume Ideas

16 DIY Book Character Costumes to Bring Your Reading to Life

50 Bookish Halloween Couples Costume Ideas