User Score: 4232
Trivia: The TARDIS and its keys being vulnerable to lava dates back to the original series episode "The Mind Robber", when a volcanic eruption threatens to destroy the TARDIS.
Trivia: Clara's birthday is November 23, the same day that Doctor Who premiered in 1963.
The train is a Class 117, which was decommissioned in 2000. (The episode was filmed on a heritage railway, accounting for the discrepancy.)
Trivia: The Doctor offers Moorhouse jelly babies. The Second Doctor ate them on several occasions and they first were seen in "The Dominators". However, they are commonly associated with the Fourth Doctor, who offered them to friends and enemies alike.
Trivia: The Doctor's use of the phrase "Are you my mummy?" refers back to the first series episode "The Empty Child," when the transformed Child used the same phrase.
Trivia: The Doctor's comment about there being so many artron emissions near Coal Hill refers back to the original series episodes "An Unearthly Child", "Attack of the Cybermen", and "Remembrance of the Daleks".
Trivia: Among the images that Psi brings up of thieves and villains are: a Sensorite, the Gunslinger, a Tereleptil, Abslom Daak from the Doctor Who comic strips, an Ice Warrior, Captain John Hart (from Torchwood), Androvax the Trickster (from The Sarah Jane Chronicles), and a Slitheen.
Trivia: The Doctor's line about Sontarans perverting the course of human history is from the 4th Doctor's first spoken words when he wakes up from his regeneration in "Robot". The 4th Doctor in turn is referring back to the events of "The Time Warrior" and his first onscreen encounter with the Sontarans.
Just after Clara leaves the TARDIS, you can see that the door is closed. During the fight, the door opens and closes.
Trivia: The Doctor suggesting that they might be in a Miniscope refers to the original series episode "Carnival of Monsters". The Miniscope is a device that gathers people and objects from a narrow period of time and stores them, allowing viewers to watch the sequence of events and repeats them as they wish.
Trivia: The clockwork robots using spare parts to rebuild a spaceship, which the Doctor can't quite remember, is from "The Girl in the Fireplace" in series 2 of the new series.
Trivia: A dinosaur walking down the Thames, albeit with much worse special effects, was last seen in "Terror of the Zygons" episode 4.
Trivia: The Doctor's reference to a scarf goes back to his fourth incarnation, who wore that piece of apparel most of the time no matter what circumstances.
When Vastra runs to Jenny's body, Catrin Stewart's eyes are clearly moving beneath her eyelids.
Trivia: The Doctor's comment about a "gobby Australian" is a reference to Tegan Jovanka, an airplane hostess and his companion primarily during his fifth incarnation.
Trivia: The observatory from "Tooth and Claw" is seen in one of the TARDIS rooms.
Trivia: The Doctor uses a crystal from Metebelis Three. The crystals were last seen in the original series "The Planet of the Spiders" in 1974: the same year this episode takes place.
The submarine's depth gauge is labeled improperly; the dial lists the units as "METEPC", or the word "METERS" transliterated into Cyrillic characters, rather than translated into Russian. The Russian word for "meters" is "метров," or "metrov" when transliterated into Roman characters.
When the submarine surfaces, breaking the ice cover, the diving hydroplanes on the sail are in the horizontal position. All submarines with hydroplanes on the sail rotate it to the vertical position before breaking the ice cover. The edge of the hydroplanes are reinforced and angled for this purpose.
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Classics, Dark Comedy, British TV, Time Travel, Creatures