Call me a dullard, but I just don't get a lot of kicks out of TV mostly. Wave upon wave of hysterically drivelled-over US dramas that inevitably end up having as much substance as the average Shophaholic novel. The seemingly nadir-free downward spiral of reality/celebrity concept programs.
Yada yada, whinge, moan you get the idea. From pillar to post, there's no meat, no thrills, nothing to grip the brain, and so you find yourself filled with self-hate and watching yet another rerun of Two And A Half Fucking Men like you're reading the back of a shampoo bottle in the shower.
Thank Christ, then, for Sherlock's executive producer Steven Moffat, who understands that a really addictive programme is not just a spectacle but a narrative puzzle every bit as fiendish as The Times' Sudoku.
His work on Doctor Who proved that he had a killer way with suspense and extended story arcs; what is the Pandoricon? Who or what is inside it? Who is River Song? Why was that crack in Amy Pond's wall so freaking scary?
In Sherlock, though, he's really coming into his own as a mind-mangler. When your protagonist is a skull-faced socially malajusted aristocrat sociopath and his nice-cop sidekick a tight-lipped army vet suffering from post-traumatic stress disorder, after all, you can't rely on human warmth to hook your viewers in.
A few people have griped about the Sesame Street-ish visual trick of clues flashing up on the screen in the first episode, A Study In Pink, from the words that rise up like steam from the dead damp body of a murder victim as Sherlock makes his synapse-whiplashing inferences - 'wet', 'dry', 'serial adulterer' - to the gleeful 'wrong!' he texts to a room full of journalists at a police press conference. But it's the perfect way to indicate that this isn't just a story, but like the original novels, also a game, in which you're expected to participate.
The denouement, of course, is designed to have you groaning out loud at your own stupidity, as the evil cabbie glowers in the doorway and Sherlock's earlier riddling musings play back in his mind: "who do we always trust, even if we don't know him? Who passes unnoticed wherever they go? Who hunts in the middle of a crowd?"
In a flash, you suddenly realise that you SAW all four murder victims get into taxis, that Holmes and Watson have already chased a taxi believing the passenger to be the murdered and ARGH IT WAS RIGHT IN FRONT OF YOU ALL ALONG. Infuriating, but also more toe-curlingly pleasurable than finally nailing that cryptic clue for 15 across.
If the second instalment, The Blind Banker, wasn't quite as exhilirating (perhaps due to a slightly obvious Chinese-smuggling premise and dodgy Banksy pastiche), the cartological cypher-games of the shadowy assassin offered the same irresistible intellectual tease of something that you can almost... nearly... but not quite figure out just before it's revealed.
The BBC are continuing the fun between instalments (well, crushingly, there's only one more to go for now) with a recreation of Sherlock's own website where you can exercise your ludic nerd-muscle in helping Holmes to decode hidden messages. It's a fun stopgap, but really, they have to make more of this series. I need it. I need it to save me from Mock The Week. Please?