Continuity mistake: When the Doctor, being held by two of the crewmen, explains that there's a geographical anomaly the sub can land on to halt its descent, the hand of the crewman holding his right arm disappears in a close-up, followed by the crewman himself disappearing in the next shot. (00:04:57)
Continuity mistake: The submarine surfaces among icebergs at the end. Just as the others go back into the submarine, the Doctor stays up there. Some snow goes onto his lip and his hair. In the following shot, we can see he isn't moving. But in the next shot, the snow on his hair and lip isn't there anymore. (00:40:00)
Factual error: The rank insignia of the Soviet officers is completely inaccurate. The captain wears the epaulets of a captain first rank (captain) and the sleeve insignia of a captain second rank (commander). Lieutenant Stephashin wears the epaulets of a senior lieutenant and the sleeve insignia of a captain third rank (lieutenant-commander). The third officer wears the epaulets of a captain second rank and the sleeve insignia of a captain third rank.
Continuity mistake: While Emma is explaining to Clara what an empathic psychic is, the Doctor grabs a bottle of milk from the table and takes a swig out of it, holding the bottle in his right hand, before jumping into the conversation to state that empaths are both extremely compassionate and extremely lonely. While he's saying this, his left hand goes from gesturing in a close-up to holding the milk bottle in a wide shot. (00:06:25)
Continuity mistake: When Clara draws the Doctor's attention to the vision of a forest appearing in the archway, the candelabra she is holding has two candles in it, with the third hole empty. Moments later, after the apparition has disappeared, there are now three candles in it. (00:15:30)
Continuity mistake: For most of the episode, there is a thunderstorm going on at Caliburn House. However, when the TARDIS is seen dematerializing and rematerializing when the Doctor and Clara go to take pictures of the ghost throughout time, it's dry in the grove where it was parked. The first time is especially noticeable, as moments later we are shown Professor Palmer and Emma looking through a rain-spattered window, commenting on the noise of the TARDIS' engines.
Continuity mistake: Before they enter the damaged TARDIS, when the Doctor watches Gregor put down Bram, and then asks Tricky why he's using a blast suit and respirator despite being an android, his hands are clasped in front of his chest in close-ups, but down below his waist in wide shots. (00:09:15)
Continuity mistake: When the Doctor begins to explain to Gregor that the TARDIS doesn't actually have a self-destruct, he places his right hand on Gregor's shoulder. In the next shot, his right arm is by his side and he isn't touching Gregor. (00:26:00)