Double Take: 'This Flight Tonight' - Joni Mitchell / Nazareth

Robert Webb's guide to pop's most intriguing cover versions

Joni Mitchell's album Blue, released in 1972, was an introspective affair. Shimmering in the album's tail-lights is "This Flight Tonight". Behind Mitchell's stripped-down jazz inflection and lonesome guitar, a pedal steel, courtesy of one Sneeky Pete, briefly miaows the sadness. Otherwise, it's just us and Joni and a vignette of stars burning up over the Las Vegas sands. "Oh, blackness, blackness dragging me down / Come on, light the candle in this poor heart of mine... Turn this crazy bird around / I shouldn't have got on this flight tonight."

The Dunfermline hard-rockers Nazareth loved Blue. You remember them: the gap-toothed vocalist, Dan McCafferty, had hair like a kitchen scourer and a voice to match. They were bad, bad boys. Among the tracks on their 1973 album Loud'n'Proud, produced by the former Deep Purple bassist Roger Glover, is a taut version of "This Flight". "We used to listen to Joni as we were travelling round in the van," recalls Nazareth's bass-player, Pete Agnew. "'This Flight Tonight' was a big favourite." They were quick to see the song's potential to rock, took it into the studio and turned it on its head. "We only wanted to do cover versions on the basis that if you can change it enough, it becomes yours. If you can't change it, don't do it," Agnew says. Their bass-heavy version leaves Joni's crazy bird taxiing on the runway.

Mitchell was impressed with the makeover: "When she was recording at A&M, we were just starting an American tour," explains Agnew. "We all happened to be in the studio the day the single was released, so we were introduced to her and told her what we had done. She said, 'What, with a rock band?'" Joni paid the Scottish band the greatest compliment after "This Flight Tonight" became a worldwide hit for them, touching down at No 11 in the UK. "She was playing a gig in London and told the audience: 'I'd like to open with a Nazareth song'!" recalls Agnew.

Nazareth still play the song, loud and proud: "It's our finishing number." The latest version features on the band's new DVD, Homecoming, recorded live in Glasgow in 2001.

'Homecoming' is available from www.nazarethdirect.co.uk