- Author's Saving Throw: At the end of "The Daleks", the Daleks are all killed off, which caused the writers a problem when they became an instant huge success. In this story, the Doctor speculate that he's gone back to a time before they all died. Later stories simply ignore it, with some Expanded Universe stories and much commentary on the show taking advantage of the "Daleks" Daleks' weaker powers and different personality to suggest that they were simply a splinter faction of the main Dalek civilisation, or surviving descendants of early experiments by Davros.
- Fridge Logic: The resistance fighters insist on leaving the area immediately after killing a Roboman, claiming that the Daleks will detect the loss of radio communication with its headgear and will rush to investigate. But Robomen allegedly commit suicide all the time, so wouldn't that leave the Daleks chasing false alarms every time one walks off a rooftop or into the river?
- Harsher in Hindsight: The Doctor's "One day, I shall come back" speech. Unless you count the Doctor Who Expanded Universe, he doesn't come back. Though they do reunite in the Death Zone on Gallifrey in "The Five Doctors".
- Hilarious in Hindsight: Peter Fraser as David Campbell bears more than a passing resemblance in this work to David Tennant as the Tenth Doctor many years later. One might be tempted to assume that Ten had time traveled back to have an adventure with One. At least until he starts hitting it off with the Doctor's granddaughter.
- Just Here for Godzilla: The story has an utterly preposterous motivation for the Dalek invasion - they want to use human slaves to mine out the Earth's molten core, replace it with an engine and drive the planet around space. The fact that they already have a massive invasion fleet is just one of the reasons why this is nonsense. However, in practice, this works fine - the serial was to be the return of the Daleks, who at the time had spawned a craze, and the audience could care less about the Doctor and his companions and wanted to see Daleks fighting people. Figuring out why the Daleks are invading takes up maybe three minutes of the plot and is mostly there to facilitate some scenes of the humans being enslaved and a fight scene with Dalek Cyborgs.
- Never Live It Down: The "jolly good smacked bottom" line had a completely gratuitous (and out of context) reference in "Twice Upon a Time", and is generally one of the first things ever brought up when discussing the Values Dissonance in '60s Doctor Who.
- Signature Scene: Without a doubt, the touching scene when the Doctor is saying good-bye to Susan, the first person to leave the TARDIS ever since he commandeered it with her, and his own granddaughter, no less. Equal parts saddening and heartwarming. It's easily one of the most widely memorable moments in the entire run of the classic series, if not the defining moment of it all, recognizable by even the people who are more familiar with the revival era, and a favourite among fans who like to make Clip Show and Montage videos of Doctor Who online. Why? It's the pivotal piece in the original run where the show really got off the ground running. So much so it rightfully deserves its own image here.
- Special Effects Failure:
- The Slyther.
- The big, beautifully designed spaceship ramp (which must have been great-looking in 1964) is ruined by how the Daleks noticeably wobble and skid as they go down it. Worse, in the climax of the episode, the Black Dalek gloats to Barbara about how their plan is flawless while its excited underlings circle it in menacing delight - tragically, one of them audibly has a squeaky wheel and sounds like one of those snacks trolleys you get on trains.
- Anybody who watches the modern DVD will probably be impressed by the flying Dalek ship it features. A pity that it's a modern CGI replacement for the original ship, which looks like a hubcap on a piece of string.
- The beautiful scene where the Doctor says goodbye to Susan is somewhat marred by how the vacuum-formed roundels in the TARDIS behind him are visibly dented and partially inside-out. That's due to the abuse the set has gone through during the past year or so of production. You'll see that in the picture on this page. Although... it may actually work to the advantage of the story. It makes sense that the TARDIS is supposed in a beat-up state after all the bad piloting and danger it's endured as of late.
- Stock Footage Failure: An alligator menacing Susan is represented by stock footage of a rather small and ineffectual-looking gavial.
- Trapped by Mountain Lions: "The End of Tomorrow" is a filler episode that instead of focusing on Barbara's plan to destroy the Daleks, mostly followed Susan making her way through a sewer pipe and getting attacked by alligators played by some rather ropey stock footage, and Ian fighting a rather unconvincing rubber suit monster which is supposedly a Dalek pet, comes from nowhere and is never seen again (especially annoying when what makes Daleks so effective is that they have never looked like people in rubber suits).
- Values Dissonance: The Doctor threatening to give Susan a "jolly good smacked bottom" is pretty jarring, as popular attitudes towards childrearing have changed from a disciplinarian approach to a supportive approach, and because serious smacking was banned in the UK in 2004. Not to mention, Susan's sixteen... It fits the Doctor's character as being old-fashioned and not a very good grandfather, but the fact that it's played for laughs is not possible today.
YMMV / Doctor Who S2 E2 "The Dalek Invasion of Earth"