The game, once more, is afoot. The world's greatest private consulting detective returns to solve another case. Anthony Horowitz is not, of course, the first to add to the Holmesian canon  the 56 short cases and four novels first collected together and published as The Complete Sherlock Holmes in 1930. There are many other books and stories that vie for inclusion, most significantly the many apocryphal writings by Arthur Conan Doyle himself not among the sacred 60: plays, commentaries, self-parodies and pre- and sub-Holmesian detectives. And then there are the many profane writings, films, and TV and radio shows based on, inspired by or otherwise deriving from the originals, ranging from the early Ellery Queen-edited The Misadventures of Sherlock Holmes (1944) to the movie The Adventure of Sherlock Holmes's Smarter Brother (1975), with a star turn by Rumpole-to-be Leo McKern as Moriarty. Naturally, some of these non-Doylean adventures are better than others: Julian Symons's ingenious A Three Pipe Problem (1975) is unjustly forgotten, the BBC's recent Sherlock rightly praised. But The House of Silk is in a class of its own: Horowitz's novel is the first Sherlock Holmes addition to have been written with the endorsement of the Conan Doyle estate. It is not a pastiche. It is not an update. It is, as its cover proudly declares, "the new Sherlock Holmes novel". Horowitz is the anointed successor. And to whom much is given, of him shall much be required 

Holmes is dead. Watson, elderly and alone  "Two marriages, three children, seven grandchildren, a successful career in medicine and the Order of Merit"  sets out to recount one of their early adventures together, on a case so monstrous and shocking he has had to consign his written account to his solicitors' vaults for 100 years. To us, the readers of the future, he bequeaths "one last portrait of Sherlock Holmes". Is the portrait accurate? Is this the Holmes we know and love?

It's 1890. We ascend the 17 steps up to the first floor of 221B Baker Street. All is as we might expect. The usual cast assemble. Mrs Hudson is there with a plate of scones. Wiggins and the Baker Street irregulars make a welcome appearance, as do rat-faced Inspector Lestrade and Mycroft ("He is still alive, by the way. When I last heard, he had been knighted and was the chancellor of a well-known university"). Moriarty ("'I am a mathematician, Dr Watson  I am also what you would doubtless term a criminal'"). Poor Mary, Watson's ailing wife. Outside, fog and hansom cabs. Inside, Holmes, with his Strad and his 7% solution.

So, all of the elements are there: the data, the data, the data. Nothing of consequence overlooked. And yet can Horowitz, like Holmes, make from these drops of water the possibilities of an Atlantic or a Niagara? Can he astonish us? Can he thrill us? Are there "the rapid deductions, as swift as intuitions, and yet always founded on a logical basis" that we yearn for?

Emphatically, yes. The characters are, as Conan Doyle himself would have them, as close to cliché as good writing allows. Horowitz's Watson cleverly excuses himself right at the start from any complaints about style or content by reminding us of Holmes's oft-stated judgment of the stories: "He accused me more than once of vulgar romanticism, and thought me no better than any Grub Street scribbler." We must take them on their own terms, then: Mr Carstairs, the troubled dealer in fine art, who is being watched by a mysterious stranger in a flat cap with a "livid scar on his right cheek". Carstairs's wife, the mysterious foreign adventuress. Cornelius Stillman, the bumptious American millionaire. The dastardly Boston Irish gang, led by the ruthless O'Donaghue twins. The madwoman in the attic. The creepy reverend who runs a home for boys. The big set-pieces: the train robbery; the escape from prison; the freak show; the high-speed horse-drawn carriage chase.

Dorothy L Sayers understood the rules of the Holmesian game when she remarked that "it must be played as solemnly as a county cricket match at Lord's: the slightest touch of extravagance or burlesque ruins the atmosphere". Horowitz plays a perfectly straight bat. This is a no-shit Sherlock.