Strike Back, SkyLuther, BBC1

There's something very seductive about predictable non-conformism on the box, and we got a double dose this week

Mavericks have been dominating the new drama on the box. In Chris Ryan's Strike Back, the much-hyped combat fest from Sky One, we had John Porter, an SAS hardman with scant regard for protocol and a score to settle. Over on the Beeb, the eponymous lead of cop show Luther was a detective with scant regard for protocol and a score to ... sound familiar?

The irony of prime-time mavericks is that their non-conformism takes a reassuringly predictable form. And yet although both John Porter and John Luther have been cooked up using the standard formula for such characters, their dramas have a long way to go to prove themselves classics of the genre.

In Strike Back we first see our man aboard a warship in the Persian Gulf in 2003, gearing up for a raid to rescue a British hostage. Everything is dramatically lit in red and, as they set off, there's lots of slapping of backs and cocking of guns and "See you back for breakfast, boys!".

War looks rather fun, in fact, until Porter comes face to face with a teenage suicide bomber and, instead of following the rules and shooting him, he cuts the wires and saves the boy's life. Two of his team are killed and when we meet Porter again in 2010 he's a divorced car park attendant with a shaky grip on life and an aversion to personal grooming.

Then a British television reporter is kidnapped by Iraqi fundamentalists and – cue portentous timpani – Porter recognises the photo of one of her abductors as the boy he spared. He blithely barges into MI6, gets himself shaved and shagged courtesy of the MoD (oh, you didn't know that they have special female officers tasked with alleviating sexual frustration?) and then back to Iraq to save the day.

Strike Back is, in almost every respect, a terrible piece of television drama. By turns predictable and far-fetched, it has the emotional nuance of a shoot 'em up computer game. Don't expect any insight into the conflict in Iraq either: it's no more than a topical backdrop to car chases and punch-ups – as evidenced by the fact that the rest of the series will see Porter shipped off to Zimbabwe and Afghanistan.

And yet, I'm ashamed to say, an unknowable part of my brain sort of enjoyed it. I didn't care about the characters, and the dialogue made me cringe, but on I watched. I haven't played a video game since I was eight, and then it was only Tetris, but I'm worried that this could be the beginning of a slippery slope.

Luther had more to recommend it. The slick, noir-ish tone was set by its Massive Attack theme tune and London looked magnificently ominous throughout. Coming from The Best TV Series in the World Ever, aka The Wire, Idris Elba has a lot riding on his turn as DCI John Luther, and he manages to wear the brooding intensity of the character lightly.

In the first part we saw Luther arriving back at work after being cleared of his part in the serious injury of a paedophile murderer he had been investigating (let's just say he didn't put himself out to prevent it). The format borrows an old trick from Kojak, in that Luther solves his case through a combination of quick-wittedness and psychology at the start of the show then spends the rest of the time trying to figure out how to prove it. So no sooner did we learn that a middle-aged couple have been shot in their home than Luther had sussed that it was their genius astrophysicist daughter what done it.

As Luther struggled to pin it on her, there was a lot of arch badinage between detective and murderess that was artificial and a tad cheesey and the whole thing felt rather crammed into its hour-long slot. Still, faults and all, it's of a quality that makes Ashes to Ashes look like a school production.