When the TARDIS lands, everyone is concerned when suddenly they find themselves wearing their usual clothes, not the thirteenth century costumes that they had been wearing since leaving Jaffa. The Doctor waves off their worries by mumbling something about the “relativity of time”, but then Vicki swears that she watched while a glass of water that she dropped and shattered on the floor reassembled and flew back into her hand. Through the TARDIS’ monitor Barbara notices that outside there are spaceships. Ian guesses that they’re in a spaceship graveyard, but the Doctor observes that the ships are all from different eras. Venturing outside, they find that, even though the atmosphere is hospitable to life, the planet seems dead. The Doctor is finally disturbed when Ian points out that, even though there is a layer of dust on the surface, they’re not leaving any footprints; worse, they find that someone or something had taken the TARDIS. Approaching a building, the Doctor and the others find two men who don’t seem to notice them even though they’re only a few feet away. Seeing various exhibits of technological devices, including the armor of a Dalek, the Doctor deduces that they’re in a museum. When other members of the museum’s staff appear, they find out that not only are they apparently invisible to the people but also the TARDIS’ crew can’t hear what they’re saying. Next Vicki and Ian discover that their hands pass through solid objects. Eventually they find that the TARDIS has been set up as an exhibit, but when the Doctor tries to enter he only phases through it. Not only that, but they see that their bodies are also propped up as exhibits. The Doctor that the TARDIS skipped a “time track” and that they’re trapped in “the fourth dimension.” He adds that they’re only looking at a potential future and to have a chance at setting things right they only have to “wait for themselves to arrive.” Soon enough the Doctor is proven to be right and the TARDIS’ crew find that they’ve actually “arrived.”
Elsewhere in the museum, Lobos, the museum’s administrator and governor of the planet under the declining Morok Empire, complains to an underling about his job and wishes that his term of office would expire faster so he could return home. Lobos is informed that an unidentified ship has arrived and worries that they may end up helping “the rebels”, but muses that perhaps the aliens can be added to the exhibit. Lobos turns out to be right; two natives of the planet, the Xerons, who have been enslaved by the Moroks, hope that the visitors have weapons. It’s a bit late, and the Doctor is captured by Morok troops, but even though Lobos has the technology to scan minds the Doctor outwits him in the interrogation, but in the end an enraged Lobos condemns him to be made into an exhibit. An attack by the Moroks forces Ian, Vicki, and Barbara to scatter. Vicki and Barbara are found by the Xerons, who explain that the Moroks wiped out most of their people and use the survivors as a slave race. A fiery Vicki encourages the Xerons to seize the museum’s armory, using her knowledge of computers to gain access, while Barbara tries to rescue the Doctor from the chamber where he’s being frozen, unaware that Ian has forced Lobos with a gun stolen from a soldier to retrieve the Doctor from the chamber and revive him. Unfortunately, just as the Doctor is taunting Lobos, a squad appears.
Barbara and Vicki are caught too and wind up in the freezing chamber with the Doctor and Ian. Barbara darkly muses that they all had four separate choices and they all seemingly led to the same conclusion. The Doctor points out, though, that their decisions may have had consequences that didn’t really change the course of fate for them, but changed the circumstances around them. Outside Vicki’s revolution is overtaking the Moroks. Lobos and all the Morok soldiers stationed at the museum are killed, the TARDIS’ crew is liberated, and the museum is destroyed. Back with the TARDIS, the Doctor finds the technical problem that caused them to skip the “time track” in the first place. Before they leave, the Doctor takes one of the exhibits, a “Space Time Visualizer.” On a nearby planet, the Daleks monitor the TARDIS’ departure and vow that their “greatest enemies” will be “exterminated”…
The Doctor admits that even he doesn’t completely understand the implications of time travel and “the fourth dimension.”
When asked by a Xeron why she wants to see them revolt so much, Vicki says something cryptic about “I have as many reasons as you, perhaps more, to want to see the future changed.” A reference to her tragic past as we saw in “The Rescue” or a hint about more of a backstory that was never incorporated into an episode? I doubt the showrunners at the time put as much planning into building character bibles and continuity as that, but who knows?
After so many episodes that barely if at all mention that the Doctor is an alien, there’s a brief indirect bit about how the Doctor, if not his entire race, has a more remarkable and durable physiology than humans. Here being almost cryogenically frozen only causes the Doctor to have an outbreak of rheumatism (and get pissed off!).
Vicki mentions how she learned about the events of “The Dalek Invasion of Earth” from her history books, which at least spells out for modern sci-fi fans, now inundated with the idea of multiple realities and diverging timelines, that, at least originally, the “future stories” in “Doctor Who” were meant to be in the future, not a future.
It’s funny reviewing an entire series like this and seeing one’s complaints being addressed in later episodes, over forty years after the fact. With this serial, Vicki does get her own adventure and proactive role, although it is a little unnerving, seeing Vicki single-handedly engineer a violent uprising. At least she’s in character as her cheerful self all the while, even once the Xerons really start mowing down the Morok troops.
Apart from Vicki taking an unexpected turn as a latter-day Pancho Villa, there’s not much else worth noting, at least that’s good. The first episode is the first time the technical side of time travel affects the story, but aside from the characters pondering fate and the possible futility of trying to avoid the event they witnessed throughout the serial very little is actually done with it past episode one. Otherwise it’s the stock “The TARDIS crew help kind, pacifistic aliens overthrow/resist other evil aliens” plot we’ve seen in quite a few non-historical serials, enough that it could be the First Doctor era’s version of the 2005 series’ “Aliens launch global invasion of contemporary Earth, but ultimately no one seems terribly affected by it” plot formula. Even the museum setting just seems like an excuse to use a set that requires nothing more than a few pieces of machinery here and there. For whatever reason the quality of the dialogue has also taken a dent, at least in the “realistically handling exposition” department, unless people really do typically remind each other of how many days are in a year according to their society’s calendar.
So, not a good serial save maybe for the first episode, but there is one point for you hardcore nerds out there: the actor who played Boba Fett is in there somewhere…