John Lucarotti's second Doctor Who script is quite different to his first; it's the first four-parter since An Unearthly Child and it's smaller in scale than most stories so far. The taut four-parter in an enclosed setting will later become something of a template for the series and this is one of the best examples of those kinds of stories.
Within the first few minutes, all four of the main characters have their place in the story established and none of them are left doing nothing, and quite significantly the job taken by each one couldn't have been done by any other. Whatever problems will beset the show in Season 19 when it re-introduces the three companion format, here the writers know what they're doing with it.
Once again, they're prevented from accessing the TARDIS, this time through the entrance to Yetaxa's tomb being sealed, but Lucarotti quite cleverly uses the dilemma as a launching point for a moral subplot. For once, a companion takes centre stage quite literally - Barbara is mistaken for Yetaxa, an Aztec god, and the travellers have to use the situation to their advantage to gain access to the tomb and thus the TARDIS. What's interesting about this, putting aside Barbara's intentions to stop the human sacrifices, is that since the TARDISeers have to go along with this and lie to/manipulate the Aztecs, it makes the "villain" Tlo'toxl, whose only concern is to destroy the perceived threat of the false goddess, quite right - they are deceivng the Aztecs, and their presence is detrimental to his people. We are only on Barbara's side because we know her.
The Aztecs is a talky script, with ideas and interweaving subplots firing in all directions. Ian gets the action side of the story as he is drafted to lead the army, butting heads with champion Ixta. Even in Aztec garb, Ian still seems like a science teacher, which I thought was quite funny, but unfortunately the fight scenes are way too choreographed.
Susan isn't in it much as Carole Ann Ford took Episodes 2 and 3 off, and Susan only appears in film inserts in those episodes. Echoing Marco Polo, Susan is in trouble for challenging Aztec beliefs by saying she would want to choose her own husband. Unfortunately, by this point Susan us such a screamer that she seems out of character when she's calm and rational.
The Doctor tries to get back to the tomb directly, by trying to access the entrance from the garden. I liked the more mellowed First Doctor and his scenes with Cameca were charming but in this plot-heavy story they seemed a bt meandering and pointless. The story would have been worse without them, but they don't improve it either, except to show us a side to the Doctor we haven't really seen before (did we really want to see his flirty side though?) and the look on his face when he realises he's just proposed marriage is priceless. I do think the continued development of the Doctor as a humorous character is a good one.
All of these plots revolve around Barbara posing as Yetaxa. This isn't Barbara as we know her, and Jacqueline Hill gives her best Doctor Who performance here. It's unclear how convincing Barbara is supposed to be as a false goddess, but given Barbara's background as a history teacher, one questions whether she would think in such black and white terms (ridding the Aztecs of the "evil" aspects of their society so only the "good" survives, thinking stopping the sacrifices won't cause an uproar). It is an important step in the character's evolution - challenging the Doctor isn't new for her, but to this degree is a surprise and few, if any, subsequent companions would dare. We know right away that Barbara is wrong, and as she puts a stop to the sacrifice in the first episode cliffhanger I was disappointed with her. It seemed as though she was actively causing trouble for the TARDISeers. The event was the catalyst for Tlo'toxl turning against her and setting the other events of the story into motion. I did enjoy the hints we got about the Doctor's past as he warns Barbara that she can't change history, and he knows that more than anyone.
Out to upstage Barbara is John Ringham as Tlo'toxl. He could well be my favourite villain of the entire series; villains are often two-dimensional because their motives and methods sometimes don't make much sense and because we're supposed to dislike them they are usually over-the-top evil. Good villains are three-dimensional and even likeable. Tlo'toxl, as I've said, goes one further and looking at the situation objectively he is totally right. John Ringham's performance is also top notch, and one can feel Tlo'toxl's frustration as he tries and fails several times to catch Barbara out, with the questions about Aztec gods and the poisoned drink. Notice too that he prefers to expose the false goddess rather than simply kill her.
Special mention goes out to Keith Pyott as Autloc, a character I really liked and sympathised with as he was the sole decent guy among the Aztecs but was the one who had his faith destroyed because of Barbara. He helped her without asking for anything in return, and was quite possibly done away with in Episode 4 for his troubles. Characters like him keep things at a human level.
The sets are great too. After not being able to see the magnificent Marco Polo sets this made up for it. The weird thing is, the set overlooking the Aztec city was clearly a backdrop by it didn't ruin my suspension of disbelief.
This is quite a rare story in that it's densely plotted and dialogue-heavy but you don't need to hear every word to follow the plot. It's one of those stories where I revel in it as the plot unfolds. For some reason I can't bring myself to only vaguely pay attention to it, I *must* hear every word. Also, somehow it seems that historical stories use better guest actors than the sci-fi stories, but it remains to be seen if it's just John Lucarotti's writing bringing the characters to life that's doing all the work.
When the TARDISeers get back to the tomb at the end, it's such a relief. Two of the stories' best moments come right at the end - the Doctor's conversation with Barbara, with her realising she was wrong, and the Doctor deciding to take Cameca's medallion with him after briefly deciding to leave it in the tomb.
Horror quotient - The show's penchant for horror was never a major factor in the historical stories. The Episode 3 cliffhanger with Ian trapped in the tunnel is the closest thing in this story.
Comedy quotient - "I made some cocoa and got engaged" The Doctor is funny in this story, but Hartnell doesn't lose his gravitas. Ian restraining Ixta with his thumb, and everybody's reactions, was also funny.
Drama quotient - The Doctor's discussions with Barbara about not changing history, not one line. Barbara's interactions with Tlo'toxl. The knowledge that if the travellers slip up they will all die - forget invasions of Earth, you really feel like they're in danger because the Aztecs are vicious and the TARDISeers have no allies.
My most-watched surviving Hartnell story. Engaging throughout with fantastic characterisation. A classic.