HOW come Oli Steadman, the South African-born bass player in Oxford indie-folk band Stornoway, has written the music for the Stephen Joseph Theatre's Christmas show in Scarborough?

In a nutshell, Oli met the Scarborough theatre's associate director, Henry Bell, through the Oxford music scene, and more particularly though Henry's brother, Adam, and his band Foxes!.

"We've been based in Oxford since 2005 and gigging for ten years now, and although Foxes! eventually moved to Brighton, we'd become friends and collaborators too after about three years," says Oli, who left South Africa when he was 15.

One Bell led to another, and so Henry has renewed acquaintances with Oli for York playwright Mike Kenny's adaptation of Hansel & Gretel. For Oli, in turn, the show marks a reunion with Scarborough.

"Five years ago, I did the music for a National Student Drama Festival production at the SJT; I was part of the Warwick University Student Drama team that did Marina Carr's By The Bog Of Cats," he says, recalling when he a wistful Irish ghost, singing the songs that won the NSDF's 2010 Cameron Mackintosh Award for Music.

"That was just one of the plays I've been involved in, as I've done plays at Oxford University and in London, but mainly as a producer."

For Hansel & Gretel, Oli has written six new a cappella songs. "We do have a cappella moments in Stornoway but we've never done it like this, where the only instrument is a glass of water: one is empty, one is full to the brim, with a couple in between," he says.

"The songs are all quite similar, sharing recurring motifs and moods, and there are certain things that come from my South African background: the complex rhythms and wide-ranging vocals.

"The African influence is like you can hear on Paul Simon's Graceland with the voices of Ladysmith Black Mambazo or on The Lion King soundtrack. It's quite an odd mix this show: we have Bavarian costumes, a Grimm fairytale story and South African music!"

Oli has a diverse musical career beyond Stornoway, ranging from his South African folk song project, Count Drachma, to writing music for BBC4's Wedgewood and Eliot documentaries and running an online concert-booking platform in London, Tigmus. Stornoway, however, gives the exceedingly tall Oli his highest profile.

"We've got to the stage where we've had success with it and we can now do it just for the love of it. Brian [lead singer Brian Briggs] lives in South Wales; my brother [drummer Rob] is in New York, and I'm in East London, so it takes some planning to get together," he says. "But we love doing it, we're very good mates and we try to do it with a smile and with the right attitude when we record."

What's more, "we hope to play Scarborough next autumn," reveals Oli. "I can't say where yet, but we hope it will happen."

Hansel & Gretel runs at Stephen Joseph Theatre, Scarborough, until December 27. Box office: 01723 370541 or sjt.uk.com