Battle in the Snow Vs Cybermen :
The TARDIS has landed at the South Pole Space Tracking station. As some of the base personal attempt to get into the TARDIS they are interrupted by a new and dangerous foe.

Get me Geneva - Quick!:
The Doctor and Polly try to reason with the Cybermen, but he cannot be swayed from his cold logic. However, it looks like Cutler has a back-up plan.

First Doctor regenerates:
The 29th October 1966 saw William Hartnell end his time-travelling adventures as he collapsed at the controls of the Tardis and miraculously transformed into a younger man

Exclusive animation
With the threat of the Cybermen foiled, Polly and Ben find the Doctor has beaten them to the TARDIS and closed the doors. As they hammer on the door, the controls operate of their own accord and the central column begins to rise and fall....

Credit: BBC Worldwide