Gnarls Barkley: 'The Odd Couple'

The Odd Couple says it all, really. Cee-Lo Green, a rapper/gospel singer whose CV includes work with Timbaland, the Pussycat Dolls and Pharrell Williams, and Brian 'Danger Mouse' Burton, the bonkers knob-twiddler who merged the Beatles' White Album and Jay-Z's Black Album to form - voila! - The Grey Album, don't make obvious musical bedfellows. However, their unlikely partnership yielded instant results in 2006, when the startling, spinetingling 'Crazy' became a worldwide number one. Though none of its other singles made even a tenth of the impact of that song, their debut album, St. Elsewhere, went on to sell more than three million copies.

Rather than striving to shake off the 'Crazy' albatross with a collection of radio-friendly enormo-hits, this second album finds the duo looking inwards - and it's not pretty. A relentlessly dark, brooding concoction of soul, electro-funk and sixties psychedelia, The Odd Couple is an unsettling listen, not least on centre-piece 'Open Book', when tribal chants combine with skittish trip-hop beats to create something truly frightening. Even the album's most accessible moment, the gospel-pop freak-out of lead single 'Run', is laced with menace, while the potentially joyous "ba ba ba" backing vocals of 'Surprise' sound sinister, not uplifting, in this context. Elsewhere the tone flits between claustrophobic, mournful and achingly intense; nothing here sounds like a smash.

Cee-Lo uses these bleak, oppressive soundscapes to investigate the murkiest recesses of his mind, wallowing in self-pity on 'Who's Gonna Save My Soul?', grappling with his potential for evil on 'Would Be Killer' and positioning himself as the ultimate outsider on 'Whatever'. Most striking of all is 'Blind Mary', on which, over the album's most memorable melody, Cee-Lo proposes to the eponymous heroine because she's the only one who'll have him. "She's my friend, she doesn't judge me," he explains. "She doesn't know I'm ugly." It's a devastatingly sad moment.

Though The Odd Couple is probably the album Gnarls Barkley intended to make - if they were aiming for the blackest interpretation of sixties psychedelia since Siouxsie and the Banshees covered 'This Wheel's On Fire', they've certainly succeeded - it can't be regarded as a complete success. Danger Mouse's production is consistently inventive, and Cee-Lo's voice remains a thing of wonder, but, ultimately, this album is easier to admire than it is to enjoy. Sometimes you need the odd shaft of light to appreciate how black the darkness really is.