Laura Marling and Friends, Royal Festival Hall, London

There's a west London alt-folk musical community that you get a glimpse of when attending Laura Marling's gigs. Tonight, Marling, who is, with her Mercury nomination last year (at the tender age of 18), the biggest star among them, has brought her friends together for a one-off show.

After a short video introducing the bashful young musicians, Marling alternates her own songs with her friends'. Not only is it a rare opportunity to hear her debut, Alas I Cannot Swim, but it is also the first chance to hear her new songs. Opener "Mama How Far I've Come" and "Devil Spoke", with its stomping beat and engaging dynamics, are examples of the rootsier and more gutsy approach Marling is taking in her follow-up album. But it's the early songs that send the crowd into ripples of applause on the opening chords, especially "Ghosts" and "My Manic and I". "Night Terror", coming later in the set, is stunning, building up to a haunting climax with Andrew Bird on violin, drums from Marcus Mumford, and cello and double bass providing rich layer of sound.

It's also an opportunity to sample some lesser-known acoustic singer-songwriters, most of whose songs move along pleasingly if not quite boasting the necessary depth and soul to linger on in the mind. Still, all fit alongside each other tastefully, although Peggy Sue's angular accordion and vocal harmony-driven "The Sea The Sea" jars with the rest of the orchestral and softly sung folk-infused songs.

Pete Roe's "Devil's Dancefloor", though early on, does well to ensure the evening avoids twee territory. Another shining star is Alessi, whose breathy vocals are a pleasing hybrid of folk singer Kathryn Williams and Björk. Her gorgeous offering "Hummingbird" compells, recalling the dreamy pop-folk whimsicality and fairy-tale world of Bat for Lashes.

Bird is another of those highlights. Older than the majority of the acoustic singer-songwriters playing tonight, and a star in his own right, his "Head Soak" is more complex by comparison, and sees him deftly move from bluesy vocals to violin (which he plucks, too), and some impressive whistling.

If there's a gripe, it's that despite the swift turnover of musicians, things are delayed by indulgent explanations. But it's so intimate and relaxed that nobody's in a hurry. An enjoyable evening.