What do Michael Caine, Peter Cook, Charlton Heston, Christopher Lee and Roger Moore all have in common? They've all played Sherlock Holmes in the movies. And now you can see some of the many other stars who've impersonated the world's most famous private detective, in a National Film Theatre season of Holmes adventures, from silent movies to ITV.
The NFT has certainly got enough stuff to choose from. Sir Arthur Conan Doyle's violin-playing, pipe-smoking, cocaine-injecting sleuth has appeared on screen more often than any other fictional character - played by nearly 100 actors, in more than 200 films, from more than a dozen different countries. The only films found in Hitler's bunker were Der Hund von Baskerville and Der Mann, der Sherlock Holmes war. Yet there's one mystery even Holmes would be hard pushed to solve - why do these static stories transfer so well from page to screen?
By rights, the cinematic Holmes should be deathly dull. Conan Doyle's yarns aren't disposable scraps of pulp fiction, but great works of literature - but they are terribly short on drama. Holmes solves many of his best cases from the sedentary comfort of his armchair. Sometimes, he doesn't even meet the criminals he unmasks. The key players in the short stories often never come face to face, and the novels are riddled with foreign divertissements and cumbersome flashbacks. There is virtually no sex, not much violence, hardly any good strong female roles, and an awful lot of middle-aged men standing (or sitting) around talking.
Most of the time, Holmes refuses to tell anyone what he's up to. Frequently, for large parts of the stories, he simply disappears. Yet the films still grip you just as fiercely as the books, because the best movies aren't about action - they're about relationships. And the central relationship between Holmes and Dr Watson is one of the classic double acts of any age.
The oldest cinematic Holmes in this season is Eille Norwood's silent private eye. Norwood was already 60 when he first played Holmes, in 1921, but he ended up playing the role in 47 films - more than any other actor, before or since. With their heavy reliance on reported speech, detailed discussion and long-winded testimony, few stories are less suited to mime, and Holmes without the words is like Elvis without the music. Yet Norwood certainly looked the part, and Holmes's creator had no complaints. "His wonderful impersonation of Holmes has amazed me," declared Conan Doyle, who continued to write these stories until 1927, three years before his death. Indeed, the main attraction of these silent films is as a record of Conan Doyle's own lifetime. The men have sunken cheeks and pot bellies, the women all look like Helena Bonham Carter, and everyone has atrocious Austin Powers teeth. Everything - clothes, skin, upholstery - looks drab and dirty. No wonder Holmes sought refuge in the needle.
TV treats include Peter Cushing (a fine performance in a rather clunking BBC production) and John Cleese in two BBC spoofs - the first with Willie Rushton as Dr Watson, in a parody by N F Simpson, and the other with Arthur Lowe as Watson. But the highlight of this season is Basil Rathbone, who made the part his own in 14 American movies, produced during the Second World War. Wartime anachronisms may taint these films for Holmes purists, but for anyone interested in the war, their propagandist spin is fascinating. The Scarlet Claw (1944) is set in Quebec, an outpost of the British empire which had been relatively reluctant to bash the Hun, and ends with a morale-boosting quote from Winston Churchill, praising Canada as the "linchpin of the English-speaking world", combining "friendly intimacy with the United States" and "unswerving fidelity to the British Commonwealth".
Even more intriguing is The Voice of Terror (1942), loosely based on His Last Bow, written by Conan Doyle during the First World War, in which he lost his eldest son. In the film, as in the book, the Bosch are still the baddies, but this time they're suave Nazis, not monocled Prussians, and the terrifying voice of the title sounds a lot like William Joyce (aka Lord Haw Haw), the Anglo-Irish Nazi who was hanged at Wandsworth Prison in 1946.
This year, there's more Holmes to come, including a new BBC Hound of the Baskervilles. "There's three things in life that are certain - death, taxes and more Sherlock Holmes movies," says the Holmes expert Gavin Collinson, one of the speakers at this season. "He has transcended the literary blueprint. He's now a brand, and as with any successful brand, people will always wish to exploit that." Poor old Holmes. He may have seen off the world's fiercest dog, and the world's most ferocious dictator, but even he is no match for the remorseless exploitation of the global film industry.
Sherlock Returns is at the National Film Theatre, South Bank, London SE1 (020 7928 3232) until 31 August
Philip Kerr is away