As a band, Calexico is perfectly named: their music is a road trip to the cinematic imagination. It takes us to Calexico, a sun-bleached crossroads where a fleapit theatre plays Sergio Leone and John Ford westerns on permanent loop. Where the panoramic horizon stares back, sometimes with dread, but mostly with hope. But Calexico's music isn't restricted to the familiar, like an indie-rock version of Ennio Morricone. It takes any route that looks promising.

From Tucson, Arizona, and almost constantly on the road, Calexico get back to where they once belonged, in their dreams. To Mexican weddings, border crossings, town squares where grandparents oversee untamed children. Then there will be a sudden, unexpected detour, and that low-stringed electric guitar switches stations from El Paso to indie rock FM. Whereas Los Lobos never forget their R&B roots, Calexico reveal a student band's cerebral self-consciousness.

A seven-piece, the band is still dominated by the two men who founded the group in 1990. Joey Burns takes the stage first, opening delicately with 'Bisbee Blue': just his Spanish nylon-stringed guitar, supported by Paul Niehaus's unshowy pedal steel. While Burns is the earnest frontman, as the evening progresses it's apparent that the backbone of the group is its drummer and co-founder, John Convertino. He is that rarity, a discreet drummer and expert backseat driver, controlling the shifts from festive dances to moody epics, never overplaying his hand.

Calexico's point-of-difference is its celebration of Mexican-American flavours, in particular the mariachi trumpets from Martin Wenk and Jacob Valenzuela. Especially effective in syncopation with Convertino, the shrill horns emphasise the Latin rhythms, and create a party atmosphere hampered by the tiered, cramped seating of the makeshift Pacific Blue "club". For the band is playing to the converted, and it is their instrumentals that get the best reaction. Guitar twangs and big-echo whistling, whip-cracks and rodeo yelps: so many cultural touchstones, conjured by musical triggers.

The more Calexico select from their Mexican musical menu, the richer the rewards. They almost transport us from our straightjacket seats, on a bleak Wellington evening, to a public party in the noonday sun.