An authorised resurrection of Sherlock Holmes is faithful to Conan Doyle.

It's a bit like meeting a very dear friend after a long, long time. You're excited and happy, of course. But you're also a wee bit anxious. What if the friend has changed terribly? What if the two of you just don't connect any more?

These are the sorts of mixed feelings that mystery buffs will experience when they pick up a copy of The House of Silk. Thrilling though it is to encounter the inimitable Sherlock Holmes again after an entire century, there's certainly cause for trepidation. For this latest mystery, set among the yellow fogs and feeble gaslights of the London of 1890, is not by Arthur Conan Doyle - the Scottish physician who created the first great sleuth of English fiction. Instead, it's been written (with the blessings of the Conan Doyle Estate) by bestselling author Anthony Horowitz. And although Horowitz and his teenage creation, Alex Rider, are hugely popular with the school crowd, there are many who question his ability to create a tale quite as atmospheric and twisted as Doyle's masterpieces. Or to come up with a faithful facsimile of the insightful and brilliant, arrogant and moody Mr Holmes.

Horowitz, however, ingeniously puts these doubts to rest. He immediately sets about creating plausible circumstances to explain the sudden discovery of the "hidden" manuscript. Like most Sherlock Holmes adventures, The House of Silk has been narrated by the loyal Dr John Watson. But in this particular case, the good doctor has waited decades before committing the story to paper. "The adventures of 'The Man in the Flat Cap' and 'The House of Silk' were, in some respects, the most sensational of Sherlock Holmes' career but at the time it was impossible for me to tell them, for reasons that will become abundantly clear, " he writes in his preface, adding that this manuscript will be placed in a vault and read only after a hundred years. "No, the events I am about to describe were simply too monstrous, too shocking to appear in print. "

By the time he gets down to writing his explosive story, Watson is a widower in a retirement home, his friend is dead and Europe is in the throes of World War I. This makes it easier for the reader to accept the slight blurring of details and the sometimes sentimental, ruminative tone of the Horowitz novel.

The story, itself, takes place at the heights of Holmes' sparkling career - and ardent fans will no doubt spot the clues and find its precise position in the canon. London is in the grip of a merciless winter and Watson, whose wife is visiting friends, is spending a few weeks at 221B Baker Street. The two friends are enjoying their tea "with a fire blazing in the hearth, the familiar smell of tobacco in the air" when a distraught visitor is announced.

This, of course, is a commonplace event in the life of the great consulting detective. But the pale and anxious Edmund Carstairs, brings uncommon danger in his wake. An art dealer by profession, Carstairs has a strange problem. He is being watched by a stranger with a livid scar and a flat cap - a man he believes has followed him home from America with murderous intentions.
This is the beginning of a tangled tale, or rather two stories that are shockingly interlinked. As Holmes starts seeking the scarred stalker, he stumbles upon another, murkier conundrum. And it's soon apparent that the secret at the heart of the House of Silk is so horrific that powerful "whispering men in darkened rooms" will go to any lengths to conceal it. Soon Holmes is in danger of losing both his reputation and his life, and even devoted readers who have endless faith in his conjuring skills will feel perturbed.

The book gallops along at an exciting pace. The mystery is absorbing. The twist at the end is clever. And, most importantly, Holmes is his familiar brooding, quicksilver self. So much so that it's easy to forget that The House of Silk has been written almost a hundred years after its companions - and to matter-of-factly squeeze it on the bookshelf between The Hound of the Baskervilles and The Valley of Fear.