She &amp; Him, Fox Theater, Oakland, California <br /> Miike Snow, Music Box, Henry Fonda Theater Los Angeles

On screen she can freeze your soul, but on stage her voice will melt your heart

Rules are there to be broken, and She & Him have jubilantly shattered one of pop's eternal laws – the one stating that Thou Shalt Not Form a Band If Thou Art a Hollywood Star Because It Will Inevitably Suck – to smithereens.

Zooey Deschanel is the Californian actress whose gamine looks, coupled with the fact that she's married to Ben Gibbard (Death Cab for Cutie/The Postal Service) have made her into something of an indie heroine, who first broke out as Cameron Crowe's super-hot cabin crew sister in Almost Famous, who twinkled as Trillian in the otherwise dismal remake of The Hitch-Hiker's Guide to the Galaxy, and whose biggest success to date came with the Golden Globe-nominated (500) Days of Summer.

The last, as chance would have it, is the in-flight movie on my flight to the States. Once you strip away its mildly avant-garde narrative structure, it's essentially an Anistonesque rom-com for people who own more than one Belle and Sebastian album, though it does have its charms. Zooey's character, however, isn't among them. Like Holly Golightly in Breakfast at Tiffany's, she's fundamentally a terrible human being who chews up and spits out the protagonist's poor romantic heart, to the extent that I enter the Fox Theater, a Hammersmith-sized 1920s Art Deco wedding cake of a venue with two huge gold warrior-buddhas glowering down over the auditorium, still harbouring vaguely negative feelings towards Deschanel herself.

These evaporate rapidly when she gambols on to the Fox's stage, banging a tambourine on her vintage-dressed hip, to front She & Him, the indie-folk duo she formed in 2008 with Portland singer-songwriter M Ward.

Coming on like a latter-day Carter and Cash or Nancy and Lee, She & Him's two albums to date consist of heart-swellingly lovely and unashamedly nostalgic melodic pop, all corny Four Seasons chords and cha-cha-cha endings, and Deschanel's high, clear voice, with a Patsy Cline yodel on the odd syllable, is a revelation.

Tonight's show is a sort of homecoming, Oakland being the city where they played their first ever gig at the Great American Music Hall, and Zooey's father, the celebrated cinematographer Caleb Deschanel, is present as is, seemingly, every indie girl in the Bay area, paying homage to their style icon.

Like a good taxi passenger, Matt Ward knows the back seat is his domain, and manhandles his gleaming Gibson in the half-light, although when he steps forward to take a line on their version of Smokey Robinson's "You Really Got a Hold on Me" in his malted cinnamon voice, every female heart in the building melts a little.

She & Him do a nice line in cover versions, and in addition to the aforementioned Motown classic we're treated to Sinatra's "Fools Rush In", Simone's "I Put a Spell on You", an incongruously kick-ass, all-guns-blazing romp through Chuck Berry's "Roll Over Beethoven", and "Ridin' in My Car" by cult power-pop band NRBQ, whose Al Anderson turns up to guest on guitar.

The duo's own material more than holds its own, particular highlights being debut album opener "Sentimental Heart" (featuring Deschanel on electric piano), the lovelorn "Black Hole" ("I'm stuck here getting misty over you/Alone on a bicycle for two") and the inspirational "This Is Not a Test", which earworms its way into my brain all the way back to San Francisco.

It's enough to make you forgive Zooey for being such a cold-hearted cow on the screen.

In front of a white-on-black jackalope silhouette, two masked men march on to a smoke-filled stage, then three, then five, then six. Even if they didn't look like the Autons from Doctor Who, Miike Snow could scarcely be any more alien and any less LA-friendly, being a synth act based in Stockholm. Then again, there's always been an element on the West Coast which gravitates towards the way we do things in Old Yurp, and the suntanned Scandophiles are out in force tonight, a not-inconsiderable show of support in a venue where it's $10 a drink and you have to pay to wash your hands.

The prime movers in the mysterious Miike Snow (the strange spelling comes from controversial Japanese director Takashi Miike) are Christian Karlsson and Pontus Winnberg aka Swedish production team Bloodshy & Avant (perhaps most notable for Britney's "Toxic"), and California-raised Andrew Wyatt.

Their epic, often overwhelming sound is simultaneously as arpeggiated as Röyksopp or Underworld and as riff-tastic as Calvin Harris. And the Angelenos aren't just here to score hipster points – there are genuine whoops for the single "Silvia" and the sweet "A Horse Is Not a Home", whose lyrics are especially apt in Smog City. ("Sometimes I swim with you in a room that is ocean sized and clear/Not here where all I breathe is smoke...")

Beneath their white plastic masks, Karlsson, Winnberg and Wyatt wear yet more "masks" (they remain part-disguised by greasepaint and Brylcreem), as though wishing to retain an element of mystique no matter how hot it gets, and never quite reveal what makes them tick. This is as cool as anything emanating from their keyboards, and I'm digging the spirit: leave 'em guessing, stay inscrutable. In my mind, I hear the ghost of Captain Mainwaring: "Don't tell them your name, Piike..."