The House of Silk, the new Sherlock Holmes novel by Anthony Horowitz, could be sub-titled "The Mystery of the Vanishing Novelist". For Horowitz's aim was "to be completely true to Arthur Conan Doyle - immerse myself in his world and be invisible in it."
Horowitz first read Sherlock Holmes at 16 and, living in Stanmore, was excited by the way that, in Conan Doyle's books, exotic happenings could reach out into the London suburbs, and naturally he was thrilled when the Conan Doyle estate approached him to write the first official Holmes book for more than 80 years. "I liked to think that I, too, could be touched by mystery."
His fidelity to Conan Doyle shows in the language of the new book - which, without being faux-Victorian, has a deliberately measured cadence - and, in the narrative: "there are no nasty surprises - you don't discover that Sherlock Holmes was once married or that Watson has a brother," says Horowitz. Nor is Holmes diagnosed as bipolar or gay and there is no silliness of the "Holmes meets Churchill" variety.
"I wanted to write an original, exciting book that would appeal to a modern audience but equally to purists. I was determined that I would never get a letter from a Holmesian saying 'how could you have written that?'" he says.
In line with 21st-century expectations, the new novel has more twists, more action - and indeed more words - than the originals, but Horowitz allowed himself only a few, modest additions to the world Conan Doyle created, such as choosing a first name for Inspector Lestrade. The cognoscenti will derive pleasure from allusions both overt and oblique to previous cases (at one point, Holmes empties his pockets and each item refers to a previous case).
And, in Horowitz's book, Watson finally receives public acclaim for his role as the detective's biographer. Holmes and Conan Doyle are both disparaging about Watson's writing abilities, so, thought Horowitz, "it would be amusing if he had become a famous writer. Watson's is a lovely voice to write in - a distinctive, honest, agreeable voice."
Honest, maybe, but accurate as a detective, no. Watson is the perfect device for misdirecting the reader - we see every red herring (and overlook many clues) through his eyes.
Although Horowitz does not intend to write another Sherlock Holmes novel, he would like to set another (original) book in the 19th-century, with "frog, growlers, gas lamps and villains"… and perhaps a walk-on part for a VIP detective.
Meanwhile, even his home displays a combination of 1890s architecture and modern edginess - a converted bacon factory, its surreal lift bears a sign urging occupants to "keep off the grass". (Confined within the steel walls, it is disturbingly impossible to obey, as the floor is carpeted with artificial lawn.)
But Horowitz is not one to let the grass grow under his feet. Now working on the second Tintin film and the last part of his Power of Five supernatural series for teenagers (getting up at 4.30am to write, because he loves it so much) he exudes contentment. And, although he still has more children's books to write, he is moving on to adult fiction - "it's exciting how Sherlock Holmes has unlocked that for me. Writing is an adventure. You have to keep on finding new mountains to climb."
