As we learn about each other, so we learn about ourselves.One of Doctor Who's few Bottle Episodes, "The Edge of Destruction" (aka "Inside the Spaceship") is a two-part oddity wedged between two longer stories. Originally, the show was confirmed for four episodes (the opening story) to be reviewed up... then it was increased to 13, two more than "The Daleks" allowed for. Worse, there was no money for sets or extras. Although it's a filler episode, the story triggers some very important Character Development for the Doctor and his friendship with Barbara.
— The Doctor begins to warm up to his companions, and vice versa
The TARDIS lurches and everyone falls over, and when they get back up again, everyone's acting a bit odd. Weird stuff starts happening and the Doctor suspects there's an alien presence on board and gets very paranoid. He accuses Ian and Barbara of sabotage, drugs their cocoa, and is himself attacked by Susan running with scissors.Turns out it's the TARDIS itself that's the problem. The Doctor hit the Fast Return Switch at the end of "The Daleks", but it got stuck and the TARDIS has been whizzing back in time to the creation of the Universe... and, therefore, destruction. The weird stuff was the ship trying to warn its crew, who fix the problem (a faulty spring; lovely 1960s space technology) and go on their way. The Doctor apologises to Barbara for having been an utter git to her, and acknowledges that she saved their lives by realising the TARDIS was talking to them all along.
- A House Divided: The main characters are stuck in the TARDIS. Outside, the ship is about to tear itself apart and inside they're at each other's throats.
- The Alleged Car: All this arc's problems are caused by a stuck button and broken spring. As the show reveals later, this module was a museum piece when the Doctor was still a young man.
- Billions of Buttons: The console's (as iconic to Doctor Who as the blue police box) caused the actors to start labeling them.◊Incidentally, on the DVDs it turns out that nobody is sure who actually wrote it. Carole Ann Ford suggests it may have been her and Hartnell during rehearsal, but she isn't sure.
- Bottle Episode: The entire story takes place in the TARDIS and its functions are shutting down, so a minimalist thing. The production crew likely needed a bottle episode at this point due to problems with the first two serials, including the first episode of each needing to be redone due to problems.
- Break the Haughty: Given that the Doctor was well into the "vicious" side of Anti-Hero in the first two stories, his behaviour here isn't very surprising. However, he reaches a new low upon threatening to throw Ian and Barbara out the TARDIS, something that could easily kill them. When the woman he threatens to kill not only gives him one hell of a What the Hell, Hero? but also figures out the problem and saves the day, the Doctor is understandably humbled. Not only does this lead to his attitude improving but sets his moral compass in a more unambiguously good direction, something that determines the show's outlook to this day.
- Character Development:
- This episode is a major stepping stone in having the Doctor's personality be more like what we know today rather than the Jerkass seen previously.
- This story begins developing the TARDIS, the first story to even hint at it being autonomous. Before this, it was mostly treated as any other time machine/spaceship; after this, writers and serials would hint more and more at it being alive, before finally being confirmed in "The Doctor's Wife".
- Early Installment Weirdness:
- Ian checks the Doctor's heartbeat and only hears a single beat. It's later established that the Doctor has two hearts.
- The Doctor scoffs at the idea that the TARDIS is sentient. The modern series in particular ran with this concept.
- Continuity Nod: As Barbra is chewing out the Doctor, she mentions the events of the previous serials.
- Easy Amnesia: Temporary amnesia affects the crew as they forgot one another.
- Eldritch Location: The TARDIS itself becomes one. This was the first hint that the ship might be alive.
- Everybody Lives: No explosions and no stabbing means no death.
- Family-Unfriendly Violence: The scene in which a strung-out Susan threatens the other characters with a pair of scissors and ends up frenziedly stabbing a mattress (see the still photo above) sparked the first of the many controversies about whether Doctor Who was too violent/frightening.
- Foreshadowing: That Susan would be the most affected by the malfunctioning TARDIS makes a lot of sense after the latter revelation of her having above-average (even by Gallifreyan standards), but far from fully trained/controlled psychic abilities.
- Midair Repair: The Doctor has to fix the TARDIS before it hits the Big Bang and is destroyed.
- Mind Screw: It's a baffling adventure inside the ship today.
- Minimalist Cast: Only the four crewmembers and the TARDIS herself.
- My God, What Have I Done?: The Doctor's been a bit of an ass until this point in time (and space), including threatening to bludgeon a caveman to death because he would've held the TARDIS crew up. But he has an epiphany at the end of this story on what a Jerkass he's been, and loosens up and becomes the Doctor we all love and know.
- No Antagonist: Unless a faulty spring counts, there is no bad guy here.
- Noodle Incident: Susan recognises a photograph on the screen as Quinnis, a planet in the fourth universe where she and the Doctor nearly lost the TARDIS.
- Not Themselves
- "The Reason You Suck" Speech: Barbara gives the Doctor a big lecture about how he cares nothing about anyone else, thinks that he is the most important person in the universe, has no sense of right and wrong, just does whatever he wants to all the time even if it endangers other people, and is a horrible man, a terrible grandfather and genuinely deserves to be dead. This leaves him quite shaken, and the final part of the serial shows him apologising to her for his behaviour and admitting that her spirit in calling him out on it is the same thing that caused her to figure out what was wrong with the TARDIS and how to save them all. This is very important in giving him Character Development.
- Reset Button: AKA The Fast Return Switch. This was the first and only time it was ever mentioned and it isn't working.
- Sinking Ship Scenario: This ship is malfunctioning and about to disintegrate.
- Slipping a Mickey: The Doctor drugs Barbara and Ian's drinks to knock them out so he can investigate what is happening to the TARDIS without interference. Ian doesn't fall for it, however.
- What the Hell, Hero?: Barbara Wright gets a great one. The Doctor is threatening to throw her and Ian out of the TARDIS, into empty space, and she tells him he has no right to threaten them as he owes his life to the two of them several times over already.
- Barbara: Accuse us? You ought to go down on your hands and knees and thank us!
- The World Is Just Awesome: At the end, the Doctor delivers a truly beautiful speech on the creation of a solar system.We're at the very beginning, the new start of a solar system. Outside, the atoms are rushing towards each other. Fusing, coagulating, until minute little collections of matter are created. And so the process goes on, and on until dust is formed. Dust then becomes solid entity. A new birth, of a sun and its planets.
- The X of Y: The firstnote of a long, Long, LONG line of such titles.