A new animated adaptation of a popular picture book to be aired over the Christmas period will be voiced by Welsh actor Rob Brydon and some of his Gavin and Stacey co-stars.

The Baddies, by children’s author Dame Julia Donaldson and illustrator Axel Scheffler, tells the story of a troll, a ghost and a witch.

Brydon, as Ghost, will be joined by Sheridan Smith and Alison Steadman, who also starred alongside him in the popular sitcom, as well as Hammed Animashaun as Troll, Robyn Cara as Girl, and Francesca Mills as the narrator.

Previous adaptations of Dame Donaldson’s books include The Gruffalo, Zog and The Scarecrows’ Wedding, which also featured Brydon as scarecrow Reginald Rake.

The half-hour special celebrates courage, kindness and the power of standing up to bullies, according to the BBC and production company Magic Light Pictures.

It follows a girl with a blue spotty hanky who moves to a cottage near The Baddies.

A mouse then challenges the Baddies to see who can steal the hanky, but they soon learn that they may have met their match in the little girl.

“The Baddies was enormous fun to write because I loved inventing these gloriously wicked characters and then thinking about what might happen when they finally meet someone brave enough to outwit them,” Donaldson said.

Sheridan Smith said it was “such a joy to be part of bringing The Baddies to life”.

“The film is funny, spooky and full of heart, and the animation is absolutely beautiful. I think families are going to have enormous fun watching these wonderful characters causing chaos this Christmas,” she said.