"I suppose that was one of the Doctor's most endearing qualities: the ability to make the bizarre and the terrifying seem utterly normal."
When Liz Shaw's friend Jean goes missing, the Doctor and U.N.I.T. are drawn to the scene to investigate. Soon Liz discovers a potential alien invasion that will have far-reaching affects on her life… and the Doctor is unexpectedly re-united with an old enemy…
Written By: Nigel Fairs
Directed By: Mark J Thompson
Caroline John (Liz Shaw), Nicholas Briggs (The Cybermen)