 The Titanic is orbiting present day Earth to observe the traditions of primitive cultures , specifically Christmas . The Doctor dons a tuxedo and joins the reception on board , meeting waitress Astrid Peth . The Doctor convinces Astrid to join him on a brief excursion to the surface of Earth . They are accompanied by married couple Morvin and Foon Van Hoff , a Zocci named Bannakaffalatta , and historian and guide Mr. Copper . While on Earth , specifically a commercial district of London , the Doctor notes that London seems abandoned , and questions a man in a newspaper stand about it . The man , Wilfred Mott , tells the Doctor that most people have left London because of the previous two years of alien activity in London on Christmas ( " The Christmas Invasion " and " The Runaway Bride " ) . 
