The Devil And Daniel Johnston, Barbican, London <!-- none onestar twostar threestar fivestar -->

It has taken 25 years, almost as many albums and a lifetime of loneliness and pain, but Daniel Johnston is finally emerging from underground cult status. Like Brian Wilson and Syd Barratt before him, the Texan singer-songwriter works in the shadow of severe mental illness. Johnston's art articulates his fragile state of mind, his childlike compositions laying bare the sadness and pain of his life.

Despite a strained voice and rudimentary musical ability, the naked honesty of his songs has drawn admirers from Kurt Cobain to David Bowie. Now he's the subject of an award-winning documentary biopic, and his comic-book-style drawings are on show in London and New York. There has been a star-studded tribute album, and now this evening of live performance.

Scottish folkie James Yorkston lets the candour in Johnston's songs of loneliness and unrequited love speak for itself, while Vic Chesnutt treats them as blues laments as he explores tunes from Johnston's 1980 debut, Songs of Pain.

Chesnutt is joined by Howe Gelb, who conjures ghostly harmonics from his guitar and plays beautiful piano as he hoarsely whispers an understated tale of unrequited love with the improbable title "Tuna Ketchup". "In the summer I worked with her in an oil refinery. She wore a yellow suit in the rain," he croons. "And I like her."

Gelb excavates the strange beauty at the heart of the songs by adding the spooky whisper of Henriette Sennenvaldt and the even ghostlier violin and saw of her Danish colleague Nils Grondahl. But he's not averse to paying homage to Johnston's playful side, hammering a toy keyboard on "Walking the Cow".

The second half is kicked off by Teenage Fan Club, who make Johnston's songs sound like their own - jangly pop - at the expense of their precious idiosyncrasy. Jason Pierce strikes a better balance, retaining their fragile beauty while investing them with the euphoria of his band, Spiritualized.

Finally, on shuffles Johnston. Without making eye contact, he unpacks his instrument and scratches away at it like a child with a new Christmas present, his quavering, cracked falsetto filling the room with raw emotion. "Without you," he sings, "Without you, I will be all right."

Although it's another tale of love lost, it's the first of the evening to be filled with hope. Things, you sense, are looking up for Daniel Johnston. He will be all right.