Dead Man’s Land is out on January 3rd. It is a novel about Dr John Watson. It might look like that I am, unusually for me, surfing the zeitgeist, with Sherlock Holmes being more popular than ever, but I realized that the concept dates back almost two years to January 2011, when I had a meeting with Maxine Hitchcock, editorial director of Simon & Schuster. She mentioned that they were looking for a work of fiction featuring a ‘detective in the trenches of WW1′. I said it was an interesting idea – what better spot to commit murder than in a place where thousands are being slaughtered each day? But I also knew it had its problems, not least because the front line was very fluid (soldiers did not spend weeks in the trenches – they were rotated back on a regular basis) and also most Military Policemen were concerned with desertion and cowardice than crime. So I said: ‘Actually, it would be better if he wasn’t a copper, but a doctor, just behind the lines, a man who might recognize a murder when he sees one. And why not go one step further and make the central figure Dr Watson?’

Why Watson? Because at the end of His Last Bow, a story written by Conan Doyle in World War One and set in 1914, Holmes mentions that Watson will be rejoining ‘his old service’, which by that time was known as the Royal Army Medical Corps. Holmes, meanwhile, will go back to his beekeeping. And so, for once, Watson is a man very much alone when he finds that there has been at least one murder out on the Western Front… and that he has been added to the killer’s list.

Dead Man’s Land is out now. Click here to buy a copy…