Eschewing the mouthy pop and cockney-accented indie of her contemporaries, 18-year-old Laura Marling is fast becoming an anti-folk sensation. Schooled by her father in the songs of Joni Mitchell and Joan Baez, and having discovered the dark delights of Nina Nastasia and Bonnie "Prince" Billy, Marling is a very modern troubadour who sings bold and literate missives from the trenches of adolescence.

Much has been made of the maturity of her music, but when Marling appears on stage, she is a typical teen. Pale-faced, her white-blonde hair glowing against a plaid lumberjack shirt and prerequisite skinny jeans set off by red ballet pumps, she bares more than a passing resemblance to supermodel du jour Agyness Deyn.

Her debut album, Alas, I Cannot Swim, sighs with the world-weariness of a survivor and speeds along with the impatience of a girl with a lot to say. Grasping an acoustic guitar, she wastes no time driving into the all-consuming love of Shine, her words simple but devastating, her angelic voice making the most of the chapel's acoustics.

But despite the upfront honesty of Marling's songs, she is painfully shy, visibly relaxing when her eight-piece band join her. Comprised of keyboards, bass, violinist, a string section Marling calls "the Fiddlettes" and multi-talented drummer and backing singer Marcus Mumford, the band bring Marling's small songs, especially Night Terror and Old Stone, to lush, sweeping crescendos.

Squirming at the idea of "standing at the side of the stage, waiting for an encore", she suffers through rapturous cheers from the crowd and following the spirited hoe-down of Alas, I Cannot Swim, she sprints away as fast as her legs will take her.