The Doctor invites his granddaughter and recently discovered great-grandson to have Christmas dinner in the TARDIS with him and Lucie. Little does he realise that a long forgotten danger is lurking in the TARDIS and somehow it is draining all of the power.
Jamie Robertson, has composed a unique choral score which is heard throughout. It includes the song Christmas Time, performed by the Poringland Singers, written by Jamie Robertson and Ian Elliot
At the end of the story the Doctor breaks the fourth wall to wish listeners a happy Christmas. This is a homage to the 1965 episode The Feast of Steven, in which William Hartnell's Doctor similarly addresses the audience.