Superworm trailer introduces Matt Smith as titular hero and Olivia Colman as narrator

The voice cast for Superworm – about the titular hero, super-long and super-strong, who is always saving the day until he gets too full of himself and is captured by the evil Wizard Lizard – includes Olivia Colman (Narrator), Matt Smith (Superworm) and Rob Brydon (Crow), Patricia Allison (Butterfly) and Kobna Holdbrook-Smith (Wizard Lizard).

"I think you always warm to stories about friendship and this is a very charming tale of friendship and self-understanding for one small worm," Smith (Doctor Who, The Crown) said.

"There's a charm, there's a wit, and there's a lightness of touch and hopefulness that fits really well into Christmas Day... I’ve never done an animation, and I read this and I thought it was sweet and interesting and fun."

Of her role as the narrator, Colman (The Crown, Landscapers) said: "I was excited to play the narrator because I love all the Julia Donaldson books. I’ve read them to my children over the years and I love watching them at Christmas time when they’re on the telly. So I was thrilled that [Magic Light] asked me.

"The films are just lovely and they come out at the time of year when you can all be cosy and at home and watching something together."

Last Christmas Day, the BBC aired an adaptation of Donaldson's Zog and the Flying Doctors.

Superworm will air on BBC One, Christmas Day at 2.30pm and will stream on BBC iPlayer the same day. If you're looking for more to watch, check out our TV Guide. Visit our Drama hub for all the latest news.