Jeremy Brett's Sherlock Holmes appeared in 36 episodes and five TV movies. Two of those were based on novels and are in Series 2 (Return), while the other three were based on short stories (huh?) and officially are in Series 3 (Case-Book) although they really come afterwards and are more of an interregnum. I'm starting to get a bad feeling about these movies. So far I've watched the first two and found them both a bit boring. Hound of the Baskervilles was okay. Its production values blew me through the back of my sofa and it made no glaring mistakes, but all my other adaptations of the same source material have more life to them.

The Sign of Four is similarly a visual tour de force. It's stunningly well made television, it really is. Everything about it is realised to perfection. The freaks are so freakish that you'll be backing away from your TV set. There are glass shots allowing Holmes and Watson to do location shoots in 1880s London. Admittedly the illusion isn't seamless in that panorama over the Thames, but it's a million times better realised than the less ambitious glass shot in The Red-Headed League. Watching this film will render you incapable of enjoying, say, the BBC's 1968 version with Peter Cushing. The most obvious difference is the length: 103 minutes against 50. It's like the difference between a feature film and a primary school nativity play.

The first notes I made were, "Who the hell are these people?" A pegleg and a midget caveman? They're creepy enough, but Thaddeus Sholto is like a shaved oran-utang who's crawled into three carpets and a hookah. He's like something from Lovecraft, if the Deep Ones had come from the Malaysian rainforest instead of slithering out of the Atlantic. His brother's just as weird. They're twins, like two ginger toads. Nevertheless Thaddeus is a good man under his eccentricities and excellent value to watch. What's more, even the lesser roles are similarly colourful. The dog-keeper is another magnificent eccentric. The killer pygmy is so grossly politically incorrect that I honestly don't know how to react. In contrast the nearest thing we have to a Basil Rathbone version (The Spider Woman, 1944) is a model of discretion and naturalism despite the fact that the actor's name was Angelo Rossitto and so was presumably wearing blackface.

Oh, and Emrys Jones is unbelievable as a mad Welsh detective. There's no obvious reason why he should have decided to play it this broad, except that perhaps he saw the tone of the rest of the production and decided he'd have to pump it up or disappear. He pumps it up. He's wonderful.

We even meet the Baker Street Irregulars! I love the Irregulars. They're part of why Conan Doyle's original novel is a particularly good showcase for Holmes himself, giving us a rich profusion of his methods of cracking a case. He can draw intellectual inferences with the best of them, but tread in some creosote and he'll be on your heels with a bloodhound. He wears disguises. He employs small children. This is a frighteningly vigorous detective and a huge part of the reason why I'm convinced that Holmes is the best fictional detective of all time.

Unfortunately the film goes on too long.

Half the problem is in the editing and half the problem is structural. The boat chase dragged for me and that could have been easily fixed with a little editorial brutality. More problematic is Jonathan Small's story. The original novel is split into two halves, as is usual with Doyle. The first half involves Holmes's investigation in England, then the second half tells us the murderer's story and why he's been hunting down the men who did him wrong. A Study in Scarlet and The Valley of Fear set their backstories in America, but this one is in India.

For me, this flashback didn't work. It's a fifteen-minute chunk at the end of the story, in which some bloke we don't know tells us things we don't care about. Maybe they could have split it off into its own mini-episode? However the puzzling thing is that I think what we got should have worked. The Granada Holmes series was always full of flashbacks. You'd get flashbacks within flashbacks. The problems with it this time might be that: (a) it's too disconnected from the story we've been watching, and (b) the filmmakers are clearly nervous about it. They know how long it is. We keep cutting back to 221B Baker Street. I'm reminded of the way in which their Hound of the Baskervilles would annoy me with pointless shots of Sherlock Holmes, serving no purpose at all except the trivial one of wanting to show us the series's star. If they'd simply trusted their material, it might have worked better.

I can't be sure, but I do wonder if those second-half backstories are the reason why the Brett movies didn't do the remaining novels. Maybe I've found the reason why Granada never did A Study in Scarlet or The Valley of Fear.

Jeremy Brett is wonderful and Edward Hardwicke is useless. Both of those statements of course go without question. I like Hardwicke's Watson... as a person. He seems pleasant. Good-natured. However consider the scenes in the previous series where Holmes cocked a snook at Watson's writing. They're glorious. David Burke always makes me laugh in them. Here Brett gets another such moment, but the production doesn't even try to make anything of it and it passes without a whimper. Incidentally this is of course the novel in which Watson meets his future wife, which is addressed here by Hardwicke occasionally saying things like, "What a very attractive woman." If you hadn't remembered the original novel, you'd never know that such a plot element was ever involved. However I will give the producers credit for making a supposedly attractive woman actually so, which has often seemed mysteriously difficult for them.

On one level, this is wonderful television. Everything about it crackles with character, even little things like the death pose of one particular man. It's exotic. I also didn't recognise John Thaw until he lost the beard. If you want to watch an adaptation of The Sign of Four, this is the one to pick. However you could also improve it no end by cutting 20 or 30 minutes out of its running time.