15 October 1966: broadcast of second episode of The Tenth Planet. The Cybermen take over the base. "Our scientists and doctors devised spare parts for our bodies until we could be almost completely replaced."
15 October 1977: broadcast of third episode of The Invisible Enemy. Leela and K9 defend the laboratory while the cloned Doctor and Leela explore the real Doctor's brain. And what is that giant prawn thing at the end?
15 October 2007: broadcast of first episode of Warriors of Kudlak (SJA). Children who play Combat 3000 are going missing; Luke and Clyde investigate and get teleported away...
15 October 2009: broadcast of first episode of Prisoner of the Judoon (SJA) starting the third season of SJA. A Judoon spaceship crashes and the evil Androvax escapes; it possesses poor old Sarah and prepares to destroy Bannerman Road.