As we celebrate mystery month and Sherlock Holmes Day tomorrow, I thought we could plunge into what makes a great mystery and crime narrative.

There are three types of mystery within the crime genre:

• Whodunits are the most traditional mysteries, where the perpetrator is hidden until the end. Examples are: Sir Arthur Conan Doyle and Agatha Christie.
• Howdunits are more police procedural and detective stories where the protagonist is tracked down. Examples are: Joseph Wambaugh and Michael Connelly.
• Whydunits deal with the perpetrator's motivation making them the protagonist. Examples are Mario Puzo’s The Godfather and Elmore Leonard.

Initially you need to choose the type of crime/mystery for your novel, so set the scene using the following:

1. Establish your detective and the crime.
2. Set up the story.
3. Show some type of reluctance of the protagonist.
4. Write a first attempt to solve the case.
5. Establish mitigating facts and create urgency.
6. Broaden the scope of the crime and investigation.
7. Deepen the detective’s backstory.
8. Establish a change where the detective realizes they're on the wrong track.
9. Reveal the criminal’s motive.
10. Find the mistake or missing piece of the investigation.
11. Solve the crime.

Before you start writing decide on the actual crime/mystery of your plot, then create a profile of your villain, your detective(s), supporting cast, setting etc. Research some realistic crimes - news stories, detective memoirs, documentaries etc. Once you have these details decide on sub-plots, which can be a number of elements, such as romance, family or personal issues, or a work situation. The more defined and relatable your characters the more the reader will enjoy the story.

Next decide on what and where you will provide clues and red herrings into the narrative. This is where research comes in creating realism of the crime. Create plot twists to keep yur readers guessing and then provide a final clue making everything "click" for the protagonist - and the reader hopefully!

My backburner crime trilogy, The Delphic Murders

has all of the above elements and I hope to get back to it at some stage,