It's the tension and affection between husband and wife Brett and Rennie Sparks that make the Handsome Family stand out from the swelling alt.country scene. Talking at cross purposes as they peer at each other through their glasses with unconcealed delight, the Sparks are Richard and Judy with George and Tammy's guitars.

Although the pair are united through a love of morbid humour and a passion for prose, their lyrical strength lies in their individuality. Where Brett writes intimately, explaining his actions and feelings, Rennie dissects newspaper stories and reassembles them using surreal images of nature and death. Brett ekes strangled notes from his guitar, never quite sure what sound is going to emerge and embracing the element of surprise. Rennie plays her hushed keyboards and gentle melodica thoughtfully. Together they find poetry in the ordinary and seek darkness around every corner.

Rennie acts as our surreal narrator, explaining the fairy-tale ideas behind each song. "This was meant to be a song about how God is on your side, but I think it's also about being a psycho," she says, her black skirt swishing over her knee-high black socks as she introduces I Know You Are There. Brett overcomes giggles from the audience as his low, husky voice evolves into a full-blown Howard Keel impression, all booming intonation and Showboat posturing. Then that fades away and he indulges in some unexpected crooning, his eyes closed, his heart lost in the sparse sounds around him. A love of the perverse is the very essence of the Handsome Family.

Rennie explains that until recently they lived on the worst street in Chicago - "Women would be vomiting into their handbags," she tells us - and were surrounded by urban nightmares. So they chose to write country songs. The theme of nature in an unnatural environment is constant, with the slow-burning rhythms and softly shuffling drums offering air despite the claustrophobic subject matter. Birds You Cannot See, from the new album Twilight, tells the story of a nursing home going up in flames and birds carrying off the survivors. All the TVs in Town reveals solitary sources of light in a city of darkness.

But it's the humour that keeps the Sparks' songs honest and prevents them from becoming sentimental epitaphs. In So Long, Brett details all the spiteful acts he committed on animals as a child. "So long to the squirrel I accidentally shot," he sings, before happily messing up a guitar solo. Soon after, he struggles with a harmonica only to throw it aside. "Dylan never did that," Rennie remarks, only half joking.

· The Handsome Family play the Wedgewood Rooms, Portsmouth (023-9286 3911), tonight, then tour.