Howling:Sarah Jane's gang and the Tenth Doctor
It's shown in SJA "Death of the Doctor" that Sarah Jane, Luke, Clyde and Rani all still remember meeting the Tenth Doctor in "The Wedding of Sarah Jane Smith." But that story took place in a version of history that's now been negated by the effects of the Time Crack from Series 5 of DW (In that timeline, aliens were fairly common knowledge, but now those invasions have been totally erased from existence). So how can they remember things that never happened? EJA 15:53, May 11, 2011 (UTC)
Aliens, even prior to the ones erased were "fairly common knowledge" for decades, but also plausibly denied. The Trickster meddling with one man's is not the same as the Daleks stealing 27 planets or Cybermen being in every home. If the invasions were negated, it's almost certainly only the big ones that altered the status quo (and that didn't occur until series 3 in Doctor Who) 90.208.84.168 17:50, May 11, 2011 (UTC)
And "The Wedding of Sarah Jane Smith" was well after Series 3 of Dr Who. Actually, aliens started to become a lot more noticeable and impossible to deny after the beginning of Series 2, with "The Christmas Invasion."