- Alas, Poor Scrappy: Adric's death. Up until that point, he'd been a fairly unlikeable character, but his death was remarkably poignant.
- Franchise Original Sin: On its first broadcast— and even today, in fact— it was a hugely popular story thanks to its action, gritty and mature feel, the return of a classic villain and the brave decision to kill off an ongoing character for the first time ever (The only companions to die prior to this were Katarina and Sara Kingdom, who had only been with the Doctor for a short time; Adric had been with the Doctor for most of two seasons). However, attempts to recapture all of these elements in future stories would play a major part in driving the series into the ground in the mid-1980s, mainly in the Sixth Doctor era. The continuity aspects were emphasized to such an extent that it led to major Continuity Lockout. This is well-shown by the Cybermen's next major story, "Attack of the Cybermen", which is basically incomprehensible without a good knowledge of Cyber-History and incredibly violent.
- Harsher in Hindsight: At least two episodes years after this have shown the TARDIS being able to materialise around people and saving them in circumstances similar to Adric's death. The latter in particular has drawn comparisons to this story. However, as the linked Radio Times article points out, neither instance involved the controls being damaged.
- It Was His Sled: People remember this story for two things: the return of the Cybermen after nearly a decade's absence, and Adric's death. At the time of broadcast, however, the former was actually a well-kept secret: the cast list for the Radio Times billed the Cyber Leader and Cyber Lieutenant as simply "Leader" and "Lieutenant" and Matthew Waterhouse was given a small post-mortem scene in "Time-Flight" so he wouldn't be conspicuously missing from the Radio Times credits. John Nathan-Turner closed the public viewing galleries for this story, and even turned down the prospect of a Radio Times cover, which would have been the first afforded to the show since 1973.
- Memetic Mutation:
- "Now I'll never know if I was right".
- The Doctor's suggestion that the Cybermen can't enjoy "Eating a well-prepared meal" has become infamous for its Narm value.
- The Doctor's line about how the Cybermen can't enjoy a "well-prepared meal" is one of Eric Saward's most notoriously feeble attempts at a Shut Up, Hannibal! moment.
- Adric gingerly pretend-typing at the climax. Matthew Waterhouse was clearly nervously anticipating the console exploding in a shower of sparks.
- Special Effects Failure:
- The impact (no pun intended) of Adric's demise is unfortunately lessened when you see the actual freighter "crash" and realize that it isn't even moving, nor does there seem to be any reason for the ship to explode. And the explosion itself seems to have been inspired by Atari games. The DVD release changes this to a more convincing CGI sequence where the freighter visibly slams into the Earth, complete with an actual explosion in the form of a pulsating, blue-white light.
- The transparent chins on the Cybermen costumes may have sounded nice in theory, reminding the audience that they're still partly organic. Unfortunately, all that it achieved was getting the story jeered at by those who thought the Cybermen were just supposed to be robots and didn't understand that the actors being visible was intentional. Even to those who do know what the production team were going for, they just end up looking like humans with silver facepaint rather than the withered husks most fans imagined inside those suits. The production team seem to have realized the concept was a failure in execution, as by the last episode most of the chins have suddenly been covered up with spraypaint, and all future appearances by this Cyberman model would have entirely opaque chins (the production notes and a short documentary included on the DVD release subsequently revealed that the voice modulator that produced the Cyberman voices inside the helmets also tended to become detached and visible through the transparent chinpieces and spraying them opaque was easier than trying to stop them from coming apart).
- In the third episode, the footage of the multiple columns of marching Cybermen was visibly created by multiple copy-pasting one column side by side.
- Tough Act to Follow: Out of the Cybermen stories in the classic era, this is the one everyone agrees is the best due to the high stakes and the death of a companion. The following stories up until the revival don't have the same impact.
- WTH, Casting Agency?: Beryl Reid as a hard-ass Ripley-esque space captain? Admittedly, she was a fine actress and did well with the role, but she didn't fit what was written in the script.
YMMV / Doctor Who S19 E6 "Earthshock"