23 October 1965: broadcast of "Small Prophet, Quick Return", the second episode of the story we now call The Myth Makers. Odysseus demands that the Doctor use his abilities to destroy Troy; Vicki is renamed Cressida by Priam; Steven is captured by the Trojans.
23 October 1976: broadcast of fourth episode of The Hand of Fear. Eldrad discovers that the planet Kastria is dead, and the Doctor manages to dispose of him. Then comes the mysterious 'call from Gallifrey', and - sob! - Sarah Jane Smith leaves after almost three years. Will they ever bring her back, do you think?
23 October 2008: answering that question, broadcast of second episode of The Mad Woman in the Attic (SJA). It turns out that the mysterious Eve had allowed Rani to wish Sarah, Luke and Clyde out of existence; Eve's parent Ship undoes the wish.