The last time I was at Village Underground, 65daysofstatic performed their soundtrack to Silent Running – the 1972 sci-fi film set on a space station after the Earth has been devastated. Tonight sees another post-rock band playing to visuals of the cosmos.

But here there is no smiling thanks from an affable, jeans-clad frontman. This is theatre. Loki and Roka, Brighton's Nordic Giants, are always in character; dressed, with capes of black feathers about their shoulders and matching headdresses covering their faces, like ancient warrior gods, they never speak, never risk breaking the fourth wall. The huge screen behind them acts as their backdrop, showing short films of damaged futures or surreal fantasies each track plays. As it's filled with images of glowing galactic formations, 'Elysian Skies' [aka 'Elysian Dreams'], the cinematic, ethereal opener of just-released debut, A Séance Of Dark Delusions, is the evening's overture; studded with brass and bowed guitar, its eerie intonations and synthesised strings swell and seep into the air.  

Under brightly coloured flashes of light, the drama continues with standout 'Evolve Or Perish'. Loki pounds the keys and bare-chested Roka frantically hits the drums, their upper bodies jerking and causing their costumes' dark plumes to perform a sinister dance of cut and thrust. The cascading piano, bombastic chords and military beats punctuated by sampled proclamations on societal collapse deal a magnificent bodyblow. It is powerful, yet delivered with a deft touch – after the music builds to majestic heights, there's a slowing, a pause for a moment of calm, before we're caught off-guard by another onslaught. The duo are expert at this, varying the pace and the density, using pauses almost like an instrument, in order to make a tiny, changing world out of a moment. On 'Dark Clouds Mean War', for instance, they manage to evoke melancholia, defeatism, strength and defiance – and all without lyrics, beyond spoken word samples. Few bands would use their work as a score to The Last Breath, a quirky horror short about a family scuba diving, but the haunting 'Through A Lens Darkly', somehow encapsulates the film in yearning motifs of piano and strings and bursting trumpet.

On the few occasions when they do incorporate lyrics (courtesy of guests, as Nordic Giants don't sing), there's a risk of losing intensity and complexity. Beth Cannon isn't here, but it's unlikely that, even live, her high-pitched, sugared vocals on 'Rapture' would ever carry enough weight. Despite its unnerving video of ragged goths in gas-masks dragging a body across the snow, the track veers towards the mainstream, abandoning the ominous in joyful waterfalls of sound, which drown Cannon. Although Nadine Wild Palmer's strident, more nuanced singing (also recorded) is better matched to the searing chords of 'Futures Dark', it still seems that the songs are eclipsed by the instrumentals.

That is, until the encore, when Alex Hedley and Billy Merrick of support Athousandfurs (formerly known as Saturday Sun) join the duo on stage for the epic 'Dissolve'. Hedley's tone is the one that Nordic Giants' output really demands – deeper and sonorous, providing a multi-textured riposte to their fragile beauty and crashing histrionics. His voice swirls with the delicate soundscape, but as the music peaks, he finds his inner Matt Bellamy and yelps to the heavens. The closer is, quite possibly, the highlight of the night. Their enigma intact, Loki and Roka walk off without a word taking their magic with them. We shuffle out, back to the far less spectacular everyday world.