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Tuesday, August 7, 2018

The Rules of Mystery Writing

The Rules of Mystery Writing - Or Are They? 

C.A. Asbrey

Ronald Knox was a mystery writer who belonged to the Detection Club, a society peopled by such legendary mystery writers as Agatha Christie, Dorothy Sayers, G. K. Chesterson, and E. C. Bentley in the early 20th century. Among his novels: The Viaduct Murder, Double Cross Purposes, Still Dead.

Knox was also a Catholic priest, which is perhaps why he was tempted to write a 10 Commandments of detective fiction. I thought it might be fun to look at these and also famous examples of where they have been soundly broken with great success.

It's generally accepted that practically all of the rules have become obsolete as society has evolved and changed. This, however, is an excellent tool for writers of historical mysteries who want to reflect times gone by. It's always fun to break rules too.

The Rules.

1.  The criminal must be someone mentioned in the early part of the story, but must not be anyone whose thoughts the reader has been allowed to follow.

One look at Goodreads will show you a myriad of modern books told from the killer's point of view.  Laura by Vera Caspary was one of the biggest hits of the 1940s and was made into a classic film noire starring Humphrey Bogart. Caspary famously said, "My agent wrote one of the worst contracts ever written. I signed it as carelessly as a five-dollar check."

Agatha Christie also uses a device in The Murder of Roger Ackroyd where the killer narrates and documents the actual denouement in a way which acts as a suicide note.

Without a doubt this rule can now be discarded and even used as a very successful device, even when writing historical mysteries.

2.  All supernatural or preternatural agencies are ruled out as a matter of course.

I'd argue that Edgar Allan Poe had already broken this rule in the Tell-Tale Heart in 1843, so this rule was already thoroughly redundant. This was further compounded by classics like Henry James' Turn of the Screw. It was first published in 1889 under the title The Two Magics. Whether or not this can properly designated a murder mystery is up for debate, but the brooding menace and overwhelming threat certainly made it an early thriller. James' work certainly did influence Benjamin Britten's work Owen Wingrave in which a ghost causes the title character's sudden death. Supernatural mysteries are now a sub genre of their own ranging from vampires, angels, ghosts to demons and everything in between 

3.  Not more than one secret room or passage is allowable. 

Someone should have told A.A. Milne when he ventured away from Winnie the Pooh and produced the classic book The Red House Mystery. This country house crime caper could have been written especially for fans of Gosford Park or Downtown Abbey. The black sheep of the family returns only to be found shot dead in a locked study. A pair of amateur detectives never rest, except for tea, in their efforts to find the truth, despite secret passageways and suspicious servants. By the 1940s, it appeared that no self-respecting large country house could hold its head up in respectable company unless it had at least one secret passage, numerous concealed doors, and a dungeon. 

4.  No hitherto undiscovered poisons may be used, nor any appliance which will need a long scientific explanation at the end.

This is another rule soundly ignored by Knox's contemporaries. The Stertton Street Affair by William Le Queux uses Orosin, a relatively unknown poison for very good reason - he made it up. Since then I'd venture to suggest that this device has been extensively used. Agatha Christie had an encyclopedic knowledge of poisons, and in her prime she released a veritable pharmacopeia of murder methods. While these are well-known to the average murder mystery reader now, these were new and complex to her readers at the beginning of her career. 

5.  No Chinaman must figure in the story.

Well, it's a good job nobody told  Earl Derr Biggers when he created Charlie Chan in 1924. As laughable as this is, it's a good indication as to how far we have moved from our great-grandparents concept of race.

It follows on from another sub rule "A servant must not be chosen by the author as the culprit. This is begging a noble question. It is a too easy solution. The culprit must be a decidedly worthwhile person – one that wouldn't ordinarily come under suspicion."

The whole thing reeks to us nowadays, but that rule was almost instantly broken by Mary Roberts Rinehart’s 1930 novel, The Door, in which the butler does actually kill his employer. This was then developed into a play which was wildly successful and gave rise to to the old chestnut, "the butler did it" which is infamous today.

6.  No accident must ever help the detective, nor must he ever have an unaccountable intuition which proves to be right.

Well, it's clear that Knox never solved any real-life murders. All kinds of accidents and intuitions have helped to snare murderers such as Lt. John Russo snaring Chanel Lewis for the murder of Karina Vetrano. The Yorkshire Ripper was caught on a traffic stop based largely on police intuition after a minor traffic infringement, and Ted Bundy was also caught in a routine traffic stop. 

7.  The detective must not himself commit the crime.

Hercule Poirot was turned into the killer by Agatha Christie in Curtain. He fakes his need for a wheelchair to fool people into believing that he is suffering from arthritis, to give the impression that he is more infirm than he is and kills the person who is manipulating others into committing murder. This continues to be used as trick to surprise the reader both openly and covertly from Double Indemnity to Darkly Dreaming Dexter to this day. 

8.  The detective must not light on any clues which are not instantly produced for the inspection of the reader. 

I actually think this one holds up, although the trick is to bury the real clues in an avalanche of red herrings and subterfuge so the mystery can't be solved too easily. It really is no fun if the reader cannot play along. A mystery is a game to be played with the reader and they'll feel cheated if all the clues aren't out there for them solve the mystery too.

9.  The stupid friend of the detective, the Watson, must not conceal any thoughts which pass through his mind; his intelligence must be slightly, but very slightly, below that of the average reader. 

I'm not sure the friend needs to be stupid at all, but a second person is a very handy way of explaining more complex matters to the reader through dialogue. It's not fair to expect everyone to be au fait with the science or forensics involved in detection.  It seems that many writers agree with me as the genre is littered with clever sidekicks. Albert Campion's burglar-turned-man-servant, Magersfontein Lugg, is able to ferret out clues and supply his master with insider gossip that comes in mighty handy when solving cases. He also has excellent criminal contacts used by his boss.  The No. 1 Ladies Detective Agency. Precious Ramotswe, the first female private investigator in Botswana, is assisted, both in and out of the office, by Grace Makutsi, efficient agency secretary and her assistant. Grace is far from stupid and aptly demonstrates the true role of the sidekick - to fill in the gaps in the detective's skill base, to show the humanity and show-case their ability to form relationships (and I'm thinking of Sherlock Holmes and Adrian Monk in that example), and to provide a sounding board which allows the detective to reveal clues and plot through dialogue. They shouldn't be there to make the reader feel superior. They have work to do. 

10.  Twin brothers, and doubles generally, must not appear unless we have been duly prepared for them. 

Good old Agatha Christie used this one in The Big Four where Poirot pretends to have (and poses as) an identical twin brother named Achille. The classic movie Dark Mirror,  also made great use of this device, as did everyone from Shakespeare to Bette Davis in Dead Ringer. Twins and mistaken identity can be great fun to play with, as long as the reader has enough clues to join in the game.

I think W.H. Auden get the last word here. It just has to be a good story.  "Detective stories have nothing to do with works of art."

New Release -- INNOCENT AS SIN (The Innocents Mystery Series) (Volume 2) by C. A. Asbrey

Nat Quinn and Jake Conroy are just doing their job—robbing a bank! But when Nat sees Pinkerton agent Abigail MacKay is already there, he knows something isn’t right. Is she on the trail of The Innocents again, or has she turned up in Everlasting, Wyoming, by coincidence?
Abi can’t believe her bad luck! Nat and Jake are about to make her true identity known, and botch the undercover job she has carefully prepared for—a job she’s been working on for months. When Jake discovers she’s cooperating with a sadistic bounty hunter who never brings in his prisoners alive, he suspects Nat might be the next target. How could Abi would betray them like this?
On top of everything else, someone has dumped a frozen corpse after disguising it as a tramp. The town is snowed in and the killer isn’t going anywhere, but can Abigail’s forensic skills solve the murder before anyone else is killed? Abi and Nat manage to admit their feelings for one another, but will that be enough to overcome the fact that they’re on opposite sides of the law?  
The Innocents and Abigail MacKay must work together to solve the murder case, but they’re still best enemies. It’s an emotional standoff, and they’re all INNOCENT AS SIN…


     It took another half-hour before Jake saw her neat, feminine figure approaching, her light blue dress standing out against the sun-parched dust of the streets. By this time, his breath came in rapid, shallow pants until his fingers prickled and his head spun. The everyday sounds of the town swamped his senses until they crashed around his skull in an echoing cacophony. Her voice reverberated, unusually strident and harsh, echoing between the screaming and shouting from years ago in his head.
     "Jake?" Abigail's eyes darted around drinking in the surroundings, looking for danger. Why greet her openly in the street, near her gate? His glazed eyes sparkled and the pupils looked enormous, but he didn’t seem drunk.
     "Abi, come with me. It's urgent."


Blog - C.A Asbrey - all things obscure and strange in the Victorian period
The Innocents Mystery Series Group 

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Links to books

The Innocents
Innocent as Sin 


  1. This was fun. Not only the 10 commandment, but the explanation of how the rules were broken. Thank you for finding and sharing these gems. Doris

    1. Thank you, Renaissance Women. It was fund finding them.

  2. Some day I would like to attempt writing a mystery, but I am somewhat intimidated by the genre at present. I wrote down the rules you listed to study later including the authors who broke the rules.
    I smiled when I read your logline for your new release. The cover is beautiful. How many mysteries do you plan to write in The Innocents series? Congratulations on your new release, C.A.!

    1. Thank you so much, Sarah. I love the way breaking the rules made for better mysteries. It was interesting to research. How many mysteries do I plan? At the moment I have done a trilogy which are being published by Prairie Rose. I can keep these going a long a there's a demand.

  3. My favorite of all Agatha Christie's mysteries are the Hercule Poirot stories. I'd be a terrible mystery writer, because I'd give away too many clues early on. lol

    1. I'm a huge fan of Agatha Christie too and I think David Suchet is just the most perfect Poirot I've seen.

  4. Christine, I admire anyone who can write a mystery and pull it off--I would flounder in writing a mystery from page one and I know it! Kudos to you, Livia, and my friend Maggie Toussaint who write mysteries so well and make us wonder "who done it" all the way through to the end! This is just an excellent post--I really enjoyed it.

    1. Thank you so much. That's one of the first questions I ask my beta readers - was it too obvious who did it!

  5. C.A.
    An interesting and amusing post. Fun reading. :-)

    1. Thank you so much. I hoped people would see it a fun.