You probably could take thephantasmagorical art pop of Bat For Lashesand resoundtrack Labyrinth with it: Hell, the 1986 Henson/Lucas/Bowie collab might even benefit from Natasha Khan’s spooky, finicky arrangements and fantasy-genre imagery. The poetry of crystal towers, emerald cities, wizards and white magic — not at all credible on paper but enchanting and believable in Khan’s hands — mesmerized a large crowd for much of last night’s show at the 9:30 Club; at other times, a brittle, more grounded Romanticism reigned. And a massive backdrop of a wolf howling against a full moon (twice between songs, Khan howled, too) stressed that despite its medievalist reveries, Khan’s album Two Suns is 2009’s best, most ambitious paean to the caprice of nature (along with its distant thematic cousin, Neko Case‘s Middle Cyclone).

To an extent, seeing Bat For Lashes in 2009 feels like seeing Kate Bush in 1985 (well, I imagine). Last night, Khan’s voice was fuller and less quirky than Bush’s, but it shared its mystifying quality, and occasionally its sensuality. And Khan’s expert touring band (like her, multi-instrumentalists all) conjured up music that, not unlike Bush’s best albums, blended precocious ideas of what pop should sound like with a pre-Renaissance ethos. Even the stage set-up — shrinelike, with statues of angels and ravens, antique lamps, and glittery accouterments — suggested a spirituality built on the bones of dead cultures.

It also nodded at the group’s aural crosspollination: Like so much music coming out of the U.K. this decade (Khan is half-Pakistani, and grew up in Britain), Bat For Lashes’ assimilates disparate sounds (hip-hop, synth pop, Minimalism) without, well, batting a lash. In “Sleep Alone” and “Trophy,” Sarah Jones’ drums were all thunder claps and whip cracks, ratcheting up tension beneath Khan’s bassy piano stomps, Ben Christopher’s nauseous synth pulses, and guitarist Charlotte Hatherley’s well-calibrated pick scrapes.

And songs like “Glass,” “The Wizard,” and especially “Daniel” balanced ambient, bare-bones moments with dramatic upward swoops; often, the band achieved catharsis with small, percussive touches — a cymbal crash, a glimmering autoharp strum, chimes dangled like rosary beads — in the little moments between verses and choruses. (The evening’s opener, the mopey Americana act Other Lives, whose set I mostly missed, also thrived on dramatic crescendos and idiosyncratic gestures.) But the evening’s unifier was Khan’s theatrical vocals, sometimes breathy or bathetic, always enunciated. Even when the songwriter wailed (like in the majestic climax of “Siren Song”), she was more narrator than songstress.

There is, of course, much that’s ridiculous about Khan’s on-record persona; the same went for T. Rex in the late 1960s, when it sang about Middle Earth. But Khan doesn’t wear her eccentricity on her sleeve. With her knowing smile, bobbing bangs, and quipping banter ( “It’s getting hot in here,” she jokily sang at one point), Khan struck a demeanor at odds with her elegiac, genre-fiction hymns. The effect was easy digestion. I’d buy her fantasies any day.

Photo courtesy of Bat For Lashes’ MySpace page.