Calexico/Iron &amp; Wine, Forum, London <!-- none onestar twostar threestar fourstar fivestar -->

Iron & Wine, aka Sam Beam, a former cinematography teacher from Miami, and the Tuscon, Arizona Tex-Mex outfit Calexico gather on an ivy-gilded stage, crowding 12 people on to it at the height of their collaborative effort. Although Calexico are headlining the tour, promoting the new album Garden Ruin, this is also a significant moment for Iron & Wine.

Beam's collaboration with Calexico is the realisation of a five-year aspiration to re-record his debut LP, The Creek Drank the Cradle, with Calexico. Beam ended up releasing what he had produced on his home computer. Iron & Wine's delicately intimate sound on that album and the follow-up, Our Endless Numbered Days (2004), is some of the most enchanting music produced in the alt.country genre. Yet perhaps this, like many brilliant moves, was an unintended turn.

The EP In the Reins, with Calexico reined in as Beam's backing band, is a departure from the whispered yearnings and lilting lullabies of Iron & Wine's albums. The grand scale of the stage and theatre alone serve to draw much more than his usual whisper from Beam, in "Sodom, South Georgia" and "Cinder and Smoke". Gradually, more members of Calexico join him on stage and the sound gets larger, with Joey Burns taking the lead vocals for "Prison on Route 41" to a fanfare by trumpeters. By way of interlude, the guest mariachi, Salvador Duran, plays solo. He stamps his feet, clicks his tongue, and adds animal sounds into his hypnotic guitar serenades.

Calexico then immerses the crowd in a grand ambience, weaving through noir guitar riffs and jazz structures with glimmering flat steel guitar, adorned with trumpet flourishes and punctuated with elaborate rhythms. They create an iconic road-movie soundscape, which crosses borders and cultures, picking up characters and instruments along the way. Yet Burns' clear country melod-ies and the band's slick professionalism veer dangerously close to MOR.

"Across the Wire" and "Sunken Waltz" are high points. After Calexico's sparkling cover of Love's "Alone Again Or" the gig comes full circle: Beam and his sister return for "In the Reins" and Duran sings his impassioned refrain. It's striking how seamless the collaboration proves. Underlining both bands' alt. status they play a laid-back, countrified rendition of The Velvet Underground's "All Tomorrow's Parties".