Sherlock: Oh, this is Mycroft, isn’t it. One mention of Baskerville and he sends down my handler to spy on me, in cognito! Is that why you’re calling yourself “Greg”?
John: That’s his name.
Sherlock: Is it?
DI Lestrade: Yes. If you’d ever bothered to find out.

There’s a Stephen King short story called “The Doctor’s Case” in which Sherlock Holmes and Dr. Watson investigate the locked-room murder of … some rich guy. I bring this up because that previous sentence and the plot of the story itself unify a number of things about the second episode of the second series of Sherlock. Stephen King, noted horror author, clues you in to the horrific nature of this episode, written by Mark Gatiss as a 21st century haunted house story, where the house in question is instead a military base in Dartmoor where they’re doing all sorts of horrid things to animals–gene therapies and weaponization, etc.

In “The Doctor’s Case”, Watson solves the crime. In “Hounds of Baskerville”, no such thing happens; Holmes solves the case as always, with Watson providing much needed data along the way. No, instead, the most pleasant thing happened while Ailish and I were watching this episode with my mum. Around twenty minutes from the end, Ailish said “I called it!” Sadly, wasn’t entirely official–she hadn’t actually said it out loud earlier–but we allowed it cos she was ahead of us by the time she did say it. Watson solves cases sometimes, too.

“The Hounds of Baskerville” is based on the next terribly famous Sherlock Holmes source this season, being the first novel-length adventure from Conan Doyle after killing the character off in 1893’s “The Final Problem”, taking place at Reichenbach Falls. I have no idea what the book is about or how any of the references were worked into tonight’s delightfully modern horror story. Sherlock still feels as classic as ever despite references to Star Trek (or perhaps because of). Even with the stem cell demonization in the story, it’s retaining its thoroughly old-school feel.

In fact, for a horror yarn, the outing is unexpectedly tame. Perhaps that’s because Steven Moffat, the writer of balls-tighteningly-terrifying Doctor Who episode “Blink” was the writer for “A Scandal in Belgravia” and that this is from the pen of Mark Gatiss, writer of “The Unquiet Dead”. I’ve yet to see any of his other episodes–CBC pushed me off the Doctor Who train a few years ago–but of the two to do a horror throwback, couldn’t they have picked the guy who invented the weeping angels? Small criticism, as the episode’s not really that bad, and is really quite frightening. Startling, mostly, but also frightening in a deeper, paranoiac sense.

It’s the second week in a row where Sherlock is feeling an unusual drought of cases, again taking to the internet for clients. A young girl writes in about her rabbit, then a young man comes down from Devon on the first train about a dog. He’s obviously shaken up about what happened the night before, and when he calls to Sherlock in desperation, saying he saw “the footprints of a gigantic hound!”, Sherlock’s interest is obviously piqued. Archaic word choice, obviously unusual. Why that one instead of dog? And yes, that’s pretty much the only reason Sherlock makes the trip up to Devon, where his friendship with John is even more strained than usual. And what about an urban myth like the hounds of Baskerville wouldn’t strain the friendship of the ultimate rationalist and his doctor friend?

Except that somehow, it winds up being Sherlock having first seen the hound and not John. Benedict Cumberbatch does an excellent job this episode continuing his portrayal of a great mind fraying at the edges due to its lack of stimulus. He’s at once a caged animal, looking for a crime, any crime to solve. Any situation at all. But he’s also a cat in repose in the sunlight, waiting for the next thing to come along. From the opening gag with the harpoon gun to the unusually intense deduction sequences this episode, Cumberbatch brings a restless ferocity to Holmes I’ve rarely seen in recent adaptations. The best comparison would be to Hugh Laurie’s House–a great mind waiting for something to occupy it. This series has seen a change in Holmes at least that much from what he was before. He’s no longer satisfied, forever on the hunt.

And somehow, Martin Freeman’s portrayal of Watson has changed to be even more stoic and unshakable. Even at his worst tiff with Holmes, he’s taking the high, silent road. John also gets a chance this week to use his much-publicized but heretofore unexhibited seduction skills on Dr. Louise Mortimer, the results of which are entertaining, indicative and funnier than any other outcome. Martin Freeman is a delight in every scene of this series where he’s present. It’s said that the core of acting is reacting–how you respond to the volleys from all the other actors on set–and Freeman can react to pretty much any thing you put in front of him. His wordless exchanges with Cumberbatch, his wordless exchanges with his coffee, his wordless exchanges with an empty room–the man puts in work and certainly earned his BAFTA for the first series.

Sherlock is a series that, for my money (having bought the first series on blu-ray and certainly importing the second series as well), has never disappointed or failed to surprise. It’s detective fiction at its finest, and “Hounds of Baskerville” is no exception. Indeed, perhaps the riskiest move of this series comes next week, with the new episode “The Reichenbach Fall”, as based on “The Final Problem”.

Dun dun DUN!