DVD 079: Revenge of the Cybermen

The time ring takes the Doctor, Sarah Jane Smith, and Harry Sullivan back to the Nerva Station, but to a period thousands of years earlier than their previous visit. The station acts as a beacon warning space traffic of the existence of a new asteroid - Voga - orbiting Jupiter. The three travelers learn that a space plague has killed all but a handful of Nerva's crew. A visiting civilian scientist named Kellman is in fact a traitor working with a group of Cybermen who want to destroy Voga!