That 'Doctor Who' continuity reference explained: Who are the clockwork robots?

New Doctor Peter Capaldi thinks back to 2006 episode "The Girl in the Fireplace". BBC

A new Doctor is in the house, but the first episode of "Doctor Who" can't help calling back to the past. Season 8 premiere "Deep Breath" sees the twelfth Doctor, played by Peter Capaldi, trying to remember a previous adventure, but his addled, post-regeneration brain can't quite remember the details -- and if you can't either, don't worry: it has been eight years. Read on to have the episode's big continuity reference explained.

Spoilers, sweetie

If you haven't seen the new episode on BBC One or BBC America yet, go and watch it on iPlayer or wherever. I'll try not to give too much away, but what follows inevitably includes spoilers. Seen it? Then read on...

"Deep Breath" sees the new Doctor take on a sinister robot, lost in time, that renews itself with the body parts of kidnapped humans. The robot is the survivor of the crashed 51st century spaceship SS Marie Antoinette, sister ship to the SS Madame de Pompadour. This rings a bell for the Doctor, and so it should: he visited Madame de Pompadour and encountered similar bodypart-snatching robots in the 2006 episode "The Girl in the Fireplace."