Timing’s a gem: through the door, down the slope, on the stairs, at the bar, cup o’ booze in clasped palm, onto floor, boom. Boris and Oxbow are missed, sadly – late nights at the office are now so commonplace that leaving on time just feels weird – but Isis are tonight’s trump card anyway, rightly topping a bill that could be neatly summarised but one way: incredible.

Breathing still rapid, chest expanding and collapsing as it’s rattled by the first bars of one of many epic rides through bombastic territories only this five-piece travel with any regularity (compare their enveloping metal-tinged soundscapes to Neurosis if you must, but the subtleties Isis possess mark them out as a far greater act than said peers), I settle and strap myself down, allowing only knee jerks and the odd slap of palm on shoulder – something of an annoying at-gig habit I’ve developed when properly into what’s unfolding before senses scattered sideways by a rare brilliance – to break an otherwise static stoop stagewards. I let go and the washes rush in; every smashed cymbal sounds like the opening gambit of some distant war; every growl that comes cascading from the guts of lead protagonist Aaron Turner threatens to spilt the ground beneath us and send us spiralling into a flaming pit.

It’s Turner’s presence, really, that has prevented Isis from climbing the ladder of commercial success a la the Mogwais of the world: tonight’s show finds them in exactly the same place as they delivered their Oceanic masterpiece from A to Z as part of ATP’s Don’t Look Back series last year, and it’s not really as full as you’d hope; recent Koko shows by bands of similarly selective appeal were rammed to the rafters. If you were to shave Turner’s acquired-taste tones from his band’s records to date you’d have a supremely skilled post-rock act inflected with overtones of chugga-metal – the sort to get stoners so space-caked off their tits that they don’t come down for a term. With them, they become one of Our Bands, one that the middlemen can’t grasp, despite the beautiful and intoxicating melodies that dance around the destructive volume of offerings from Panopticon and In The Absence Of Truth, their past two long-players proper. The power they display is too mighty for accurate conveyance via the written word; Isis have to be felt to be believed, and only those braving those vocals for an hour plus are blessed by the force of an act who are still one of the finest, one of the most instantly memorable, on the global tour circuit.

Of course, the majority of those in tonight leave – after a skull-splintering encore of ‘Celestial (The Tower)’ featuring a mercifully clothed Eugene Robinson of Oxbow – with grinning mouths plastered unevenly beneath sweaty brows; a select few can be heard muttering something about shit sound, but if you’ve ever seen a show at Koko you come prepared and overcome the obstacle. It’s what Isis do, magnificently: blast through all barriers in their path with sets that not only burn the ears but scorch the depths of the faithful souls before them with such regularity that one can only gape, awe-struck vacantly, at their mastering of a music that balances grace and grandeur with amazing heaviness on such a fine knife-edge.

The blade’s so sharp it could slice steel; Isis are so intense that, on their day (when don’t they have one?), they can shatter the stuff into sand-sized grains.

Photograph by Damon Allen Davison (click for link)