Taylor Swift left British actor Shaun Dooley awestruck when she surprised him as he recorded a cover of her tune Never Grow Up for a new Children in Need charity album.

In a new BBC documentary, which chronicles the recording of the album, Got It Covered, Swift reveals her boyfriend, Joe Alwyn, received a text from his The Favourite co-star Olivia Colman, asking if he could help arrange the big surprise.

The popstar jumped at the chance to stun Colman's Broadchurch castmate, cutting short his performance from the control room at Abbey Road Studios and asking him to sound "more American".

Dooley put his hands over his face as he realised he was speaking to the woman who wrote the song he loves as Swift made her way into the studio for a hug.

Revealing she was a "big Broadchurch fan", she also thanked him for singing one of her songs and told him it sounded lovely, adding, "I can't sing this song live because I wrote this song about moving out and realising I wasn't going to be a kid any more. The fact that I heard you were dedicating this to your family, my heart doubled in size."

Swift wasn't the only big music star who staged a surprise during the recording of the album - Coldplay stars Will Champion and Jonny Buckland stunned Doctor Who actress Jodie Whittaker as she rehearsed their hit Yellow.

The stunned actress confessed she felt like she was 13 again as she stood before the rockers, who then revealed they would be joining her on the track in the studio.

The documentary about the recording of Got It Covered aired in the U.K. on Wednesday. The album, which also features performances by Colman, Dooley's Broadchurch castmate David Tennant, Helena Bonham Carter, and Luke Evans will be released next month.