12 June 1965: broadcast of "Journey Into Terror", fourth episode of the story we now call The Chase The Tardis crew and the Daleks explore a house filled with apparently supernatural creatures. (Frankenstein's monster was played by the father of a college friend of mine.)
12 June 1969: last filming of the last episode of The War Games, Patrick Troughton's final appearance as a regular (though he came back three times afterwards).
12 June 1971: broadcast of fourth episode of The Dæmons. The Doctor is captured by the villagers, but escapes; meanwhile the Master summons Azal.
12 June 2010: broadcast of The Lodger. To save the Tardis and Amy, the Doctor must pose as a human lodger in a house where the folk upstairs are not what they seem.