- Recycled Set: Mickey's flat is the same set as Jackie's and Rose's.
- What Could Have Been:
- Originally, the TARDIS brought Rose back home just minutes after she departed, much to her surprise - rather than arriving a year too late.
- Jackie was originally meant to accompany the Doctor and Rose to 10 Downing Street.
- Originally, this episode featured the discovery of a buried "alien" spacecraft in a construction lot in Tottenham. It was only as production loomed that Russell T. Davies began to realise what could be achieved with CGI, and so rewrote his scripts to provide greater scope for the introduction of the "alien", with the ship's destructive crashlanding now part of the narrative. Davies also elected to feature a live "alien" in the story, rather than just a corpse which would turn out to be nothing more than a shank of beef.
Trivia / Doctor Who S27 E4 "Aliens of London"