Overview: Joining the host for this festive edition are Britain's Got Talent judge David Walliams, talking about his new family comedy The Boy in the Dress, veteran actress Barbara Windsor, current F1 world champion Lewis Hamilton and 8 Out of 10 Cats host Jimmy Carr. Ed Sheeran, one of the year's most in-demand singer-songwriters, chats and performs, and there's also music by Idina Menzel, the Snow Queen from Disney's Frozen.