Plot hole: When Jamie and Cully go on the offensive, Jamie lures a quark away from a drilling site into a narrow valley, then Cully drops a boulder onto it. Yet when we see the crushed quark, it is next to a drill, on flat land.
Plot hole: The map of the "War Zones" where the Aliens are conducting their War Games can be seen several times in this story. The map is visibly divided into 11 zones. Yet, during this story, the "War Zones" visited or referred to total THIRTEEN.
Revealing mistake: (Ep. 4) After Omega takes off his mask and looks in the mirror, when he sees that his physical body doesn't exist he puts his mask back on and screams, but when he shouts, "If I exist only by my will, then my will is to destroy," Omega's mask pops up off his face, and we can see the actor's blackened face as he shouts the last bit of his dialogue. (00:07:10)
The Doctor: This is a situation that requires tact and finesse. Fortunately, I am blessed with both.
Trivia: Such was the popularity of Doctor Who in Britain in the mid-1960s that even the Beatles wanted to make an appearance in the show. So a scene was written into "The Chase" to allow them to appear. The idea had been devised of including a scene on the Time and Space Visualiser depicting a Beatles fiftieth-anniversary concert in 2015, with the Fab Four dressed up as old men. John, Paul, George, and Ringo themselves were interested in the proposition, but it was vetoed by their manager, Brian Epstein. It was then thought that an appearance by the Beatles on Top of the Pops might be used instead, but no such footage was available. Fortunately, the Beatles were scheduled to perform "Ticket to Ride" at Riverside Studios in Hammersmith on April 10th, 1965, and that footage was used instead.
Earthshock - S19-E6
Question: In Earthshock, season 19, at the end of episode 3, the Cyber Leader views his troops marching down the corridor. Each column is headed by a Cyber Leader. Is this a mistake, or is there more than one Cyber Leader allowed per army?
Answer: In 'The Five Doctors', three separate Cyberleaders are definitely used. So it's likely that Cyberleaders are like unit commanders, of which a fair-sized army might have several.
Daria Sigma