Director David O. Russell tracked down Electric Light Orchestra leader Jeff Lynne while he was dreaming up the soundtrack for his 1970s-era movie American Hustle and asked him to part with a handful of unreleased tracks.

The Silver Linings Playbook filmmaker had been told that Lynne would never hand over the never-before-heard tunes, but Russell was feeling lucky, thanks to his former post code.

He explains, "He (Lynne) happened to have a song called Overture 10538, which turns out to be the zip (post) code where I grew up, which is a freaky thing. I never actually talked to him about that, but he loved the film and gave these unreleased tracks to us.

"It's magic to have classic-sounding songs, which have never seen the light of day. Long Black Road and (Lynne's version of Debussy's) Claire De Lune are tracks that have been sitting on a shelf for over 20 or 30 years. I love using songs that are overlooked and not to be taken seriously."