1)This is the last of the "intact" First Doctor stories, and watching it, you can feel the winds of change blowing for the show. The "Swinging 60's" make their presence felt for the first time in the show - it's a bit of a contrast with the show's hitherto somewhat "old-fashioned" milieu. There are other "mod" touches as well - particularly the "computer" font used for the episode titles. In alot of ways, I think of this as sort of being a "Pre-UNIT" story, set in (then) contemporary London, with the Doctor acting with the cooperation of the government and the military. In fact, it's actually a little surprising how easily the authorities accept the Doctor, since up until now he's always been something of an outsider. In the novelization there's a scene added in which forges an introduction for himself, but in the episode itself they just sort of accept him. Hartnell's quite good in this, especially considering that he was nearing the end of his tenure. He's a formidable presence here. I found the bit with the "Out of Order" sign on the TARDIS amusing.
2)Poor Jackie Lane, she doesn't really get much of an exit here - just sent off for a rest early in the second part, never to be seen again. Shame, really, I always liked her in the show. Apparently, she didn't end up haivng much of an acting career after this, and ended up becoming a theatrical agent, a common fate for former Who girls.
3)We also meet Ben and Polly, who don't make much of an impact as characters in their first story. Ben comes across as a bit more likable than Polly in this first outing. We get another shift here, as Polly is the first new young female companion who doesn't fit the "substitute for Susan" role.
4)In WOTAN ("Will Operating Thought ANalog") we get the first of many rogue computers that the Doctor will encounter over the years. Interestingly, it seems to be Skynet's "dad", since it seems to pretty much have the same motivations. I wonder if Cameron was a Doctor Who fan? The War Machines are rubbish as "Terminators", though - try as they might to make them seem formidable with that seemingly interminable fire-fight in the third part. Actually, they're more like proto-Daleks, although a good deal more awkward. There's a swell screw-up in one of the testing scenes, where a War Machine shoots at a guy and obviously misses wildly, but the guy obligingly keels over anyway.
5)Much is made of the Post Office Tower here, with the Doctor beign a good deal more impressed by it than it might seem to merit. I gather it was quite new back then, and something of a wonder in its day. It's called soemthing else now, I think - the BT Tower or some such.
Episode 1: "Doctor Who is required. Bring him here." This story marks the only time in the show's history that the Doctor is called "Doctor Who" as though it was his name. This is generally treated as a screw-up, and in the novelization it is changed to "The Doctor". Still, Skynet WOTAN did seem to know what "TARDIS" stood for, so maybe it had inside info. I kind of like Catherine Tate's joke that the Doctor's name is "Keith Who", and he keeps it secret just because he doesn't like it.
Episode 2: A War Machine corners Ben!
Episode 3: The Doctor confronts a War Machine! Hartnell looks particularly impressive here.
Episode 4: Ben and Polly enter the TARDIS!
This is one of my favorite First Doctor stories. Since I haven't seen "The Smugglers" or "The Tenth Planet", this feels for me like a real "Last Hurrah" for William Hartnell. One can really sense that a seismic shift in the way the show is presented is coming up fast.
[Part of list of Doctor Who episodes here.]