Other mistake: The Fisher King says "The Time Lord... Lied." The subtitles say "The Time Lord... Night." (00:35:00)
Other mistake: The line spoken is "You mash up Vikings to make warrior juice." The subtitles say "You must have [...]." (00:12:30)
Revealing mistake: In several episodes of season 9, starting at "Under the Lake" and continuing through "Before the Flood", "The Girl Who Died" and "Sleep No More", the same white hallway model is used. For the first two episodes, this makes sense, since they play in the same location. However, the same hallway is used in "The Girl Who Died", when the men from Ashildr's village get blasted to death, and again in several scenes in "Sleep No More" when the characters run through the hallways. Also, it seems the control room from the underwater research center, where the characters hide from the ghosts in "Under the Lake" and "Before the Flood", is reused as the white room in "Hell Bent" when the Doctor pulls Clara out of her timeline, though in "Hell Bent" the room is nearly empty and the room in "Under the Lake" and "Before the Flood" is full of equipment.
Revealing mistake: At the end when the Doctor makes it snow, in the wide shot you can see the snow blows in from the left side, showing that they used a snow machine just off-camera. (00:54:30)
Revealing mistake: When the Doctor goes to toss the trio of Christmas balls up, the two times after the first toss are re-used shots of the first toss. His movements of his right arm to bring up the controller are too exact to be coincidence. (00:50:15)
Visible crew/equipment: As the Doctor tries to get Donna to jump to the TARDIS, as the camera is in a close up on her in the taxi, the yellow camera vehicle is reflected on the cab's paint. (00:12:50)
Visible crew/equipment: On the Moon's surface, the camera and boom mike can be seen reflected on the visor of the astronaut as she talks to Clara.
Time Heist - S8-E5
Continuity mistake: After Delphox taps on the glass to awaken the Teller, her fingers close as her hand drops below shoulder level. After the angle change, her hand is above shoulder level, index finger extended. (00:06:03)
Other mistake: As the Doctor passes a stack of three cubes, the camera is close enough to see the top cube has two small squares intertwined on the side facing diagonally toward the light. He said all were the same, no difference or individuality whatsoever. (00:03:53)
Continuity mistake: As the Doctor talks to Idris/TARDIS, he reaches into his coat. When the angle changes, he reaches in again. (00:18:20)
Continuity mistake: After River shoots the last of the Silence, she turns her gun flat side out, and muzzle up. After the angle change, she does it again. (00:37:58)
Continuity mistake: When the file with the photo of Amy's arm lands in the circle, the thumb in the photo is above the 'T' in 'THIS'. A moment later, the photo's position has turned 180° so that the thumb in the photo is pointed the other way. (00:02:57)
Revealing mistake: As Amy stands where she is told, a cable comes towards her feet. As it does, a black thread can be seen pulling it up to wrap around her leg. (00:21:39)
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: As Amy first enters the TARDIS, the Doctor comes up from her left, says his line, and leaves from her left. When the angle changes, he passes in front of her from her right.
Continuity mistake: On the alien ship, when the Doctor is told the bad news about the bus, his hand with the phone drops to below chest level. Then it's suddenly at chin level. (00:32:30)
The Sontaran Stratagem (1) - S4-E4
Visible crew/equipment: As the Doctor tries to get Wilfred out of the car, the camera goes to follow his movement and there is a reflection of the lighting rig and camera on the car.
The Sontaran Stratagem (1) - S4-E4
Revealing mistake: In the beginning, the ATMOS system takes the car to the Thames, then runs it into the river. At first, the car runs forward normally. After the angle change, there's a huge white cloud of mist behind the car that dissipates quickly, meaning an air cannon of a sort was used to propel the car into the river. (00:02:35)
Continuity mistake: The cables on the window washer's bucket are fine until Foster shines her sonic pen on it. In the close up, the spot on the cables looks to be already cut and of course wired with the pyrotechnic device. (00:26:15)
Chosen answer: No, no information is avalible for the identity of the entity.
Repo_Man