SO, YOU’RE a successful award-winning vocal group, planning a big Christmas single, and you want to make sure it’s a hit. What do you do?

If you’re Blake, you call in one of the biggest guns possible – Dame Shirley Bassey.

The Welsh diva teamed up with multi-platinum selling three-piece Ollie Baines, Humphrey Berney and Stephen Bowman for single The Christmas Song (Chestnuts Roasting on an Open Fire) on their new festive outing, reasonably called A Classic Christmas, which they are now touring, with a date at Didcot’s Cornerstone Arts Centre tomorrow (Thursday).

And Shirley will be there too, kind of – the boys sing a “virtual duet” with the music legend, whose visage is projected on a screen above the stage.

The band’s Ollie tells how they hit upon the song.

“We listened to Dame Shirley’s most recent recordings, as well as her past albums, watched a lot of YouTube clips from dozens of live shows, then started to compile a shortlist of about five songs,” he says.

“We felt sure that Dame Shirley could make a hit out of any of the songs on our list, so we sent it over and let her choose the one that she liked best – which was The Christmas Song.”

Blake play the Cornerstone, Didcot, tomorrow. Tickets are available at cornerstone-arts.org.