Grinderman, Garage, London<br/>Karen Elson, Bush Hall, London

Mature is for cheeses. His new band do deranged gonzo garage rock and hypnotic voodoo blues

The traditional line on the "mid-life crisis" gets it wrong by a full 180 degrees.

Invariably, what's being witnessed isn't sad desperation but, rather, sudden liberation. Some time in the past 10 years, Nick Cave must have experienced a moment of clarity. Maybe he was sitting at a piano singing one of the Bad Seeds' uniformly excellent but just slightly dull 21st-century ballads. "Wait a minute," he surely thought, "this isn't me."

Of course, to find or re-find your true self, it often helps to pretend to be somebody else. Nick Cave invented his badass, Mexican-moustached Grinderman persona. And he invented Grinderman the band, essentially a reshuffle of the Bad Seeds, but favouring deranged gonzo garage rock and hypnotic voodoo blues over mature, contemplative balladry. It's been a revelatory reclamation of his mojo, and has fed back into the Bad Seeds themselves: for three albums, in one guise or another, Nick Cave, 53, has been on fire.

Clean of chin and crisp of collar, widow's peak swept back above that severe brow, Cave's ditched the original Grinderman image tonight, though his band still sport Amish-style facial topiary. And he delivers as physically intense a performance as he's given since the beautiful chaos of The Birthday Party, all sudden karate kicks and dying-bird flutters, frequently losing it completely: at one point during "Heathen Child", issuing the demand "give me the money!!!" like some dollar-eyed sideshow preacher, he realises he's been screaming into an empty mic stand.

He has a fine foil, too, in Warren Ellis, a man whose beard will never not look as though it's held on by elastic, breakdancing like he's panhandling for pennies and whacking the bejesus out of some cymbals with maracas that look like a butternut squash.

For all Grinderman's savagery, there's delicious humour amid the debris. How about "My baby calls me the Loch Ness Monster/Two great big humps, and then I'm gone..." for a self-deprecating couplet? Grinderman are at their best, though, when sexual frustration and comedy simmer up together. On the awesomely slow-burning "Kitchenette", Cave half-threatens, half-promises "I'll stick my fingers in your biscuit jar and crush all your gingerbread men", his bony fingers miming the action. The atypically straightforward love song "Palaces of Montezuma" is dedicated to Cave's wife Susie who, he tells us, is in the audience. "Who's got the kids?" someone heckles. "We sold them," Cave retorts. "Cheaply." He turns his back for a second, then reconsiders. "We ate them."

Last week, a spray-tanned single mum from Yorkshire was crucified by the red-tops after appearing on The X Factor when it emerged she had been working as a call girl. Her evident desperation to make a better life for herself, coupled with the tabloids' appalling handling of the story, is why I'll be rooting for Chloe Mafia for the rest of the series. It's also, tangentially, the reason I find it hard at first to root for Karen Elson, a porcelain-skinned, copper-curled model from across the Pennines in Oldham.

You'll know Elson for her turn as the Victorian-frilled apparition in The White Stripes' "Blue Orchid" video. She is, you see, Mrs Jack White, which can't have done her any harm when it came to bagging a recording contract with XL, the label which also has the Stripes on its roster.

Elson's chosen genre – country – used to be the music of the downtrodden, but is now the sound of privilege. We're clearly intended to view this enterprise seriously, as signalled not only by the respectable record label but also by the ornate Bush Hall, home to "proper" singer-songwriters.

She makes a pretty good fist of it, in fairness. Her half-decent Nashville voice has a nicely tremulous timbre on the lower notes, and her band do a neat line in cha-cha-cha endings. The high-water mark of Elson's material is a bal-musette waltz called "A Hundred Years From Now", but her choice of covers is tasteful: Wanda Jackson's "Love", Donovan's "Season of the Witch" and a Sandy Denny-esque ballad, "Geordie" ("bridle me my milk-white steed" and what have you).

Ultimately, it's hard to divine exactly what Karen has proven, besides anything Zooey can do, she can do... almost as well. But I suppose you can't blame Elson for parlaying her status into a parallel career. She's just working what she's got, like everyone.

Next Week:

Simon Price watches live performance kill the video star as, 30 years late, The Buggles play their first concert