We all know there’s Sherlock Holmes references scattered in Doctor Who, and here’s another one from tonight’s episode!

Bolt holes! Sherlock Holmes had a series of “hide outs” where he would go for cases or if he needed to go into hiding/get away. These were called bolt holes. They were also referenced in BBC Sherlock’s His Last Vow, where Mrs. Hudson suggested one was behind the clock face of Big Ben, in an homage to The Great Mouse Detective.


Also the actress who played Journey Blue was the one who played Sally in the unaired pilot. Remember, there’s only seven actors in Britain.

- Curly