On This Day... 3rd October

Under the Lake was first broadcast on this day back in 2015. 

Four years before, viewers to CBBC would have seen the opening episodes of the fifth and final series of The Sarah Jane Adventures - a story called Sky, which introduced what was supposed to be a new regular character, replacing Tommy Knight's Luke Smith. This was a sombre experience, as the series was being broadcast posthumously, Lis Sladen having passed away earlier in the year.

Also worth noting, 3rd October 1985 saw the broadcast of the episode of The Lenny Henry Show in which he played the Doctor, up against a Cyberperson named Thatchos, based on the then Prime Minister.