The Bells of Saint John - S7-E8
Continuity mistake: When the Doctor says "I'm an alien from outer space, I'm a thousand years old, and I can't fly a plane! Can you?", the sonic screwdriver jumps from his right hand to his left. (00:26:43)
The Bells of Saint John - S7-E8
Continuity mistake: When the Doctor rides the bike out of the TARDIS, visible in the background is the TARDIS with the door still open. In the very next shot, the door is closed. (00:28:47)
The Bells of Saint John - S7-E8
Visible crew/equipment: When the Doctor and Clara are riding through London on their motorbike, the camera rig filming them is visible in their helmets. (00:29:05)
The Bells of Saint John - S7-E8
Continuity mistake: When the Doctor and Clara are sitting at their table on the balcony, talking, the level of Clara's mostly-finished milkshake changes several times, most noticeably when she and the Doctor are arguing over who is going to use her computer to hack the bad guys' systems. (00:31:00)
The Bells of Saint John - S7-E8
Continuity mistake: When the Doctor and Clara, while seated at their table on the balcony, are arguing over who has the better hacking skills while pulling her computer back and forth, in overhead shots their table is somewhere in the middle of the balcony. This contrasts with all other shots, which show their table right next to the railing. (00:31:16)
The Bells of Saint John - S7-E8
Continuity mistake: When the Doctor hands the scone to the waitress, her grip on it changes between shots. (00:33:00)
The Bells of Saint John - S7-E8
Factual error: Clara determines the location of the enemy's base of operations: floor 65 of The Shard. However, there are multiple issues with this conclusion. Firstly, floor 65 is a residential property, not an office location; offices in The Shard occupy floors 2 through 28. Secondly, the view of 30 St Mary Axe from Miss Kizlet's window puts the office below 180m, the height of the latter building. This would mean the office must be below floor 50. Finally, when the Doctor rides his motorcycle up the side of the building, 30 St Mary Axe is again seen, this time significantly below his location, and on the wrong side of The Shard. Not only then does the office's height change, but also which side of The Shard it is on. (00:36:06 - 00:38:40)
The Bells of Saint John - S7-E8
Visible crew/equipment: After Miss Kizlet enters her office to find the walking base station Doctor sitting at her desk, as she walks around the motorbike lying on the broken glass, when this 'Doctor' says, "Yes, those still with bodies to go home to would be free," we can see the moving reflection of two crew members on the surface of the motorbike.
The Bells of Saint John - S7-E8
Continuity mistake: When the Doctor and Clara are on the rooftop terrace, there's a distinctive design on the Doctor's bow tie, but when he's in the coffee shop the bow tie's design differs, and when he runs outside to ask if Clara's okay it changes back, then it changes again when he's in back the shop. Additionally, when the walking base station Doctor uploads Clara it's wearing a bow tie, and its design also changes on the motorbike and in Kizlet's office.
The Bells of Saint John - S7-E8
Visible crew/equipment: When on the motorbike, the camera vehicle and equipment is reflected on the Doctor's helmet.
The Bells of Saint John - S7-E8
Factual error: The view from Ms Kizlet's window was taken somewhere in the vicinity of London Wall eg. the Museum of London, not from The Shard.
Continuity mistake: After the Doctor gets hit in the head by a football, when he raises his arms defensively when Ellie Oswald comes over to see if he's all right, his arms switch positions between the wide shot and the close-up. (00:02:02)
Revealing mistake: While the Doctor and Clara visit the market in Akhaten, the rubber mask of one of the aliens they encounter is revealed, as the eyes of the actor wearing it are very much visible. (00:08:10)
Continuity mistake: The leaf Clara feeds the Old God, which was the catalyst for her parents meeting and which she kept tucked in her book as "page 1", looks completely different to its first appearance in "The Bells of Saint John".
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: When Skaldak grabs Professor Grisenko's head and announces that Martian law decrees the destruction of the Earth, his hands change position on Grisenko's head between shots. (00:31:47)
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)
Chosen answer: 1) When Stephen Moffat took over he ignored a lot of what had been developed before (there is not in-universe answer). 2) It would have killed Rose, so the Doctor absorbed the energy. His body regenerated before the energy could do a significant amount of damage that would prevent regeneration.