David Tennant is teaming up with another veteran of Doctor Who for a new animated children's television programme.
Sophie Aldred, who played Ace alongside Sylvester McCoy as the seventh doctor, is going to be the voice behind Tree Fu Tom in the CBeebies series of the same name, about the adventures of an eight-year-old boy who is transformed into a hero by putting on a magic belt.
David will play his sidekick, Twigs, in the show, which follows the pair's adventures in a magic world called Treetopolis.
CBeebies controller Kay Benbow said: "We have a fantastic cast on this show who work brilliantly as a team. Their rapport permeates through to the programme reflecting the characters as a group of friends working together.
"We are delighted to have David on board as part of the team. The physical energy in his performance works so well for animation and his sense of fun and cheeky humour will delight the older CBeebies audience.
"We have many incredibly talented actors on CBeebies - in shows and the Bedtime Hour - because the very young deserve the very best. It's about seeking out great performances and offering the best possible quality to our viewers."