Girls, Sky Atlantic, Monday Hatfields & McCoys, Channel 5, Thursday Elementary, Sky Living, Tuesday

Lena Dunham’s much-hyped series Girls proves as cringingly funny and truthful as promised

Jemima Kirke, Lena Dunham and Zosia Mamet star in Dunham’s caustic series (HBO)

'I think I might be the voice of my generation," aspiring writer Hannah Horvath announces in Girls. "Or at least a voice, of a generation." It is a downsizing entirely appropriate to a show in which low expectation is a leitmotif.

The central character, Hannah (played by Lena Dunham, also writer and director of the show), has quit her unpaid internship of two years; has a boyfriend who wants her only for her body – and even that in the most debasing way – and who undermines her attempts to find a new job with an outrageous rape "joke"; and is surrounded by friends who, despite apparently having more going for them, are similarly beaten down by the post-recession blues of New York life.

There's Jessa, the apparently glamorous, bohemian English jet-setter who is, in reality, a self-deluded, scrounging baby-sitter. There's Jessa's cousin, Shoshanna, who, unable to conceive of herself as an individual, defines herself by means of Sex and the City characters: "I'm definitely a Carrie at heart, but sometimes Samantha kind of comes out."

And there's Hannah's room-mate, the apparently perfect Marnie, who sees herself as a mother hen but can't even get her own life in order; so repelled is she by her boyfriend because he's too nice that she creates "stranger" fantasies to be intimate with him.

Yet this troubled background is the perfect setting for Dunham's blazingly caustic script. She writes as kinetically as Sorkin and as spontaneously as Tarantino. And best of all, it feels utterly real. There are none of the forced punchlines of the average sitcom, no need for a laughter track – just squirm-inducing scenes and cracking lines such as, "Sorry she didn't turn up to the lovely abortion you threw for her," which, believe me, is funnier on screen.

Girls has been accused of being racist on the grounds of there being no black face among the cast. But to say that is to miss the point: Dunham is writing about the narrow world view and experiences of four white twenty-somethings with a sense of entitlement who struggle to perceive anything outside the self-constructed bubble of unreality in which they live. And this she does quite brilliantly.

Another import that was much hyped in the US before coming over here is Hatfields & McCoys, which takes its cue from what is, in America, a legendary post-Civil War feud between two families. To those of us who don't know the story, however – and I'll wager that's the vast majority of British viewers – it is essentially a revenge drama: you killed one of our'*, so we's gonna kill one of your'*.

In the first of a five-parter, Kevin Costner and Bill Paxton struggle manfully as the heads of the families to make the drama seem more substantial, but with alcohol and guns combining in most every scene, the action lurches from one overly dramatic spectacle to the next. A girl falls in love with a boy from the other family; bloodshed. A pig is stolen; bloodshed. Someone looks at someone funny; have a guess. And the spitting! It's a wonder anyone has any phlegm left.

While I have no problem with anti-heroes – Girls is full of them – here, it's hard to care about anybody or anything; no one seems to have any honour, or to deserve respect. Maybe that's the point. But it doesn't make for compulsive viewing.

Unlike Sherlock, of course: Steven Moffat and Mark Gatiss's retelling of Holmes's greatest tales has been one of the great successes of recent TV seasons, so one wonders what the American makers of Elementary were thinking. Jump on the bandwagon? Take them on at their own game? Well, that's something they certainly don't do, because this is different in every way from its British predecessor.

Playing much like Monk, only set in the Big Apple, it sees a wired Jonny Lee Miller and his sidekick, Joan Watson (a nicely understated Lucy Liu) picking up on all the clues the flatfoots overlooked. Their first case was all twists within twists rather than a real brain-teaser, and the outcome, hinging on a bag of rice, lacked élan.

But while it bears no resemblance to any of Conan Doyle's stories and is more your basic procedural with some unlikely moments of deduction, Miller's charismatic presence is enough to make it CSI-level watchable; enjoyable, then, rather than a joy.