Early Who tried to rotate between “historical” and “sci-fi” episodes, something foreign to this Who watcher for whom actual time-traveling into the past was a rarity for Doctors 3-5 (although this has thankfully been revived for the new episodes). So after visiting the Marinus, the travelers set down in ancient Mexico. This immediately made the episode interesting for me, as I am an archaeologist by trade, and the Aztecs are more unfamiliar to most western viewers than even the Cathay of Marco Polo.
John Lucarotti wrote this story, and Marco Polo as well, so it’s interesting to compare them. This is actually the third ‘travel into the past’ serial, if you count An Unearthly Child. In the first two, the travelers were separated from the TARDIS and the story was relatively simplistic, if at times convoluted: find the way out of there. The Aztecs is much more interesting, as it adds a twist. No longer are the party mere passive observers. The Aztecs poses a much more interesting conundrum: can one change the past? If one can, do you have the moral obligation to try and prevent what you perceive as morally wrong behavior. And if you can’t (or won’t), does that make you an accomplice to the crimes you witness?
The Aztecs begins with the TARDIS setting down in a historically inaccurate combined pyramid temple/tomb, belonging to the high priest Yataxa. As possessor (via theft) of the high priest’s bracelet, Barbara is understood as an avatar of the priest, and a semi-divine being. She appears in the midst of a struggle for power between the priests Autloc and Tlotoxl. The latter is the High Priest of Sacrifice, and looks unkindly upon Barbara’s attempts to stop the practice. Autloc is more flexible (and perhaps more manipulable). (Note: The sacrifice is to bring rain to quench a long drought, so the god being sacrificed to is likely Tlaloc, though I don’t think this is mentioned in the episode).
The main story involves the party trying to find a way to get back inside the pyramid, to the TARDIS, and Barbara’s attempts to change Aztec culture from the top down. Through it all, Tlotoxl (played in an over-the-top Shakespearean fashion by John Ringham) works behind the scenes to expose Barbara as a fraud and to kill the travelers.
A subplot involves Ian’s enlistment as an Aztec officer and his struggle with the rather stupid warrior Ixta, who feels the honor should be his. Another involves Susan’s arranged marriage to the wonderfully named Perfect Victim. Most of these are dull and tedious, the only amusing moment coming when The Doctor inadvertently proposes marriage to the wise woman Cameca by giving her a cup of cocoa, which she accepts. The Doctor’s first wife!!
While the fighting scenes are comical and Ixta’s incompetence more farcical than suspenseful, Barbara’s struggle with her unexpected position — and responsibility — are far more interesting. For once, she is the center of a story, and Jacqueline Hill plays the role well. I think that Barbara intuitively knows that her efforts to stop the practice of human sacrifice are a fool’s errand, but her persistence is reasonable and helps develop her character. In fact, I find everyone’s nonchalant acceptance of their impotence at the end rather off-putting. Even admitting the impossibility of changing a culture overnight, I would have a hard time taking it all in stride. Should Barbara have let the sacrificial rites go on before her, observing them as was her role, without lifting a finger? Isn’t that rather cold-blooded? The episode leaves these questions hanging, for the viewer to ponder after the fact.