Doctor Who Christmas special: Jenna Coleman to return as Clara Oswald amid leaving rumours A preview during Children in Need on Friday showed Clara meeting Peter Capaldi's Doctor for what might be a final closure meeting. Clara. I want you to step inside the Tardis. I don't want you to talk. I want you to do as I ask. Please," the Time Lord says in the festive teaser clip, which also features Nick Frost as Santa Claus. "I know what this is, I know what's happening and I know what's at stake," the Doctor tells Santa ominously. Natalie Gumede, Michael Troughton, Faye Marsay and Nathan McMullen will all guest star in the special. The Doctor Who series finale, which aired last Saturday to an audience of 5.45 million, saw Clara and the Doctor part with a goodbye hug, prompting many to believe that she would not be returning. Speculation that Coleman is leaving Doctor Who has been rife in recent months, but the actress has so far refused to give anything away. "We've sat down with (showrunner) Steven Moffat and we've all decided we don't want anybody to know which way it's going," she told Radio Times in September. If you know I'm in the next series or if you know I'm off, you'll know how the story ends. Read more: Interview: Doctor Who star Jenna Coleman Jenna Coleman on Doctor Who: 'There's a big surprise coming' Doctor Who Christmas special clip airs during Children in Need