The Evil of the Daleks - S4-E9
Continuity mistake: (Animated version). Waterfield puts down the photo of the Doctor on his desk but the next time we see his desk the photo is no longer there and then later it's back on the desk again, without Waterfield having moved it.
Continuity mistake: At the beginning of episode 3 when the Doctor tells Ace that she can do what the Cheetah People can, he puts his hand on her shoulder. In the next shot his hand is no longer there, but it's back again in the next.
Continuity mistake: When Karra dies and turns back into her human/humanoid form she is wearing a black top that they did not wear as a Cheetah Person.
Remembrance of the Daleks - S25-E1
Continuity mistake: When the Doctor and Ace steal the military van they leave the doors open, but in the next shot when we see the van leaving Totters Lane the doors are suddenly closed.
Continuity mistake: The Doctor's hair goes from being messy and extremely curly in the TARDIS scenes to being combed and much less curly in the scenes set outside the TARDIS.
Continuity mistake: When the Doctor picks up the humanoid skull his hat is looking normal but in the next shot the brim of his hat is folded down and completely flat. In the next shot it's back to not folded again.
Continuity mistake: In episode 4, Skinsale is murdered by the Rutan on the stairs right outside the crew room but later in the episode when the Doctor and Leela runs down the same stairs, Skinsale's body is not there.
The Masque of Mandragora - S14-E1
Continuity mistake: When the Doctor is explaining about the Mandragora Helix, his scarf goes from being over his shoulder, to behind his shoulder and back.
Continuity mistake: When the Doctor enters the desert room in addition to his coat, he is wearing a brown waistcoat with a white shirt underneath. When the shot cuts away and the back to the Doctor, we see him take off his coat but he is no longer wearing the waistcoat. Later when he collects his coat after the acid bath scene and he starts to look through the wardrobe for a disguise he is mysteriously wearing the waistcoat again.
Continuity mistake: Towards the end of episode 2 it's nighttime, but when Ian and the Doctor lure the Dalek over from the TARDIS, and when it falls, it's daylight.
The Ambassadors of Death - S7-E3
Continuity mistake: In episode 4 a UNIT sentry (Max Falkner) is seen shooting at one of the ambassadors when he is killed, but in episode 6 he is alive and well and is seen again in the 1976 story "The Android Invasion" , this time as a corporal.
The Daleks' Master Plan - S3-E4
Continuity mistake: In the cliffhanger to episode 1 of this story, as The Daleks approached the TARDIS, the TARDIS door was open. At the beginning of episode 2, seconds after the cliffhanger moment in 1, the door is suddenly closed. (00:01:00 - 00:02:00)
The Sontaran Experiment - S12-E3
Continuity mistake: In Episode 2, when the Doctor calls Harry from the Control Room and Harry enters the room next to the Cryogenic Chamber, there is an oblong yellow panel next to the door. It extends from about Harry's waist line to about 200mm below the top of the door. But in Episode 3, when Noah calls Vira from the control room part way into his transformation, and everyone runs into the adjacent room, the panel is mounted differently. It now extends from about Harry's mid-torso, to the top of the door frame. (00:03:35 - 00:09:32)
Chosen answer: The Master is insane. If he can't control the universe, he'd rather see it destroyed.
Captain Defenestrator