WARNING: THERE ARE SPOILERS AHEAD IF YOU'VE NOT SEEN THE GREAT GAME YET!

Here's a note to any writers currently pitching a television show, who want to lay down one or two threads to help convince a TV executive to commission series two as soon as possible: watch the last ten minutes of Sherlock.

Because, surely, therein lies a textbook example of how to do it. After spending over four hours building up to the introduction of Sherlock's infamous nemesis, Moriarty, you not only get a really quite unnerving face-off, but you then get left on a great cliffhanger, with so many questions waiting to be resolved. Heck, if I was a BBC executive previewing the episode, I'd be pressing the recommission button right there.

The obvious thread awaiting resolution? Well, it's just how will Sherlock and Watson get out of this one. If Sherlock shoots the explosives, then surely they all go up, and while I'm confident he's got a cunning plan, or spotted something I haven't, chances are there's the best part of a year to wait yet. Gah.

What's more, there's the identity of the people behind those laser sights, too. Who else is hiding away in the swimming pool? And while we're here, what a great place to have such a showdown, and what a wonderful rug-pull writer Mark Gatiss pulled. Even appreciating that some of you will have seen it coming, the tempo of that final scene was just brilliant, and the fact that it stopped, and then suddenly restarted again with the re-emergence of Moriarty, was terrific television.

And while we're talking about Moriarty, just what's going on with his voice? Because if the intention of writer Mark Gatiss here was to put him across as a genius nutter, then the portrayal here has certainly delivered the goods. There's a little bit of the channelling of Heath Ledger's Joker in there, I thought, and yet we've only been given a glimpse, a mere tease, of the character. A cracking tease, too. I'd personally bundle Messrs Moffat, Thompson and Gatiss in a room together right now, and not have them re-emerge until three more scripts for next year have been produced. And mark Moriarty top of their priority list, too.

Yet, The Great Game wasn't an adventure just about the last ten minutes, and interestingly, it didn't follow the same formula as the two stories we've seen thus far. Whereas A Study In Pink and The Blind Banker have given us one case apiece to get our teeth into, here Holmes and Watson have to bash their way through several before they can get to the end of level boss. That means that Gatiss' script doesn't quite have the level of detail behind each individual case, as he instead leaves enough crumbs visible for Sherlock to do his work, but not too much on top.

In some ways, it's not dissimilar to the structure of Angels & Demons, and the subsequent Tom Hanks-starring movie that was based on it. But there's a crucial difference: Angels & Demons wasn't any good, and The Great Game really was.

It helps, for the sake of the narrative here, that this story has come last out of the three, as we're au fait by now with the modus operandi of Sherlock and Watson. We know how Sherlock will read a scene to get his clues, and it's a shorthand that aids the pace of The Great Game. This is far more Sherlock's adventure than Watson's this time too, and the onus is very much on him to do the heavy lifting. That said, Watson has plenty on his plate too, not least his interactions with Sherlock's brother, and also the continuing evolution of his romantic entanglement with Sarah. It's a story that manages to squeeze a lot into its 90 minutes.

It's traditional at this point that we stop to salute the two leads. Appreciating we're hammering home the point week after week, Benedict Cumberbatch and Martin Freeman have been just terrific in the main roles. They've been an inspired casting choice, both as individuals and, crucially, as a partnership too.

Back to the story, then. The cases that the pair work through here are quite dark, and there's an underpinning sense of urgency throughout them, aided by some on-screen graphics of numbers gradually going down. And by the time we get to the end of the adventure, there's little doubt that Sherlock has been tested a lot.

For example, take a look at the minute he has to identify that the painting in front of him is a forgery. The explanation that he comes up with in the end is both brilliant and difficult to spot, and anyone who's managed to guess the resolutions of the previous two stories in advance would, I'd wager, really have struggled with that one. The police must have been relieved they had a consulting detective at hand, at least.

I guess there's a (very) little bit of me that would have liked just a drop more depth to the cases that Sherlock whizzes through here, yet I fully accept that Mark Gatiss' script is terrifically paced, and his balancing act is a very tricky one. As things stand, it's hard to grumble with the quality of episode he's put together, and you get enough to get your teeth into, in the build up to the big finale.

It's hard to grumble too with just how Paul McGuigan's direction makes use of it. I thought his handling of A Study In Pink was just outstanding, one of the best-directed TV shows I can remember seeing in some time. Here, he too has to go a little quicker than he did first time round, but it's again a measured, often-still piece of work, and all the better for it. He lets you see what's going on, and the momentum of A Great Game is hard to fault. Plus, McGuigan's direction of that final scene was utterly spot on.

In short, The Great Game is a very strong end to a series that's been an absolute treat, even better for arriving in the middle of the summer, where quality new television drama is extremely rare. Maybe one of the ramifications of this show's success is that more broadcasters will be willing to give July and August a bit more love. That'd be a great legacy for the show right there.

Still, what's especially wonderful about Sherlock, even putting the terrific cliffhanger aside for a minute, is how brilliantly poised it is. After all, we have meaty characters just three stories in, and there's a wealth of further Sherlock material to attack. I'm quite happy with the thought that I'll grow old watching Cumberbatch and Freeman solve case after case in the ensuing years myself, and I sincerely hope that the BBC commits to a long run of these. My head overrules my heart in wishing that it's kept to three or four stories a year at best and no more (a Christmas special one year would be lovely, too), but as far as I'm concerned, the countdown to more Sherlock starts right now.

To all concerned: congratulations on the new television triumph of the year. Now please go and make some more.

Read our review of Sherlock: The Blind Banker here and A Study In Pink here.