The audio readings of the novelisations of the classic Doctor Who stories are absolutely and utterly brilliant, and this is no exception. William Russell (Ian in the original series) reads John Lucarotti's novelisation of his own story first broadcast in 1964, only the sixth story of the first season of Doctor Who.
Ian and Barbara are still newbies in the time travel world, and Barbara, finding herself mistaken for the returned spirit of the great god Yetaxa, sees this as a chance to persuade the Aztecs to stop their blood sacrifices, and hopefully avert the awful fate she knows is theirs in just fifty years time with the arrival of the Conquistadores. The Doctor, sadly, knows there is nothing she can do to change history, but Barbara has to learn this lesson herself.
Meanwhile, Ian is taken to become an Aztec warrior and incurs the envy of Ixta who wants to be the chief warrior himself; Susan, Yetaxa's handmaiden, rebels against the rules of the Aztecs and is used as a pawn by the High Priest of Sacrifice, the ghastly Tlotoxl, in his schemes to remove all the time travellers from his path. It's up to the Doctor to try and find a way where they can all safely get back to the Tardis and leave; but circumstances don't make this easy.
This is a fantastic story; it's long enough that we get to really know the main characters; not only the Doctor and the Tardis crew, but the priests, the warriors and the lady Cameca, and those who give themselves in sacrifice to their gods. The twists and turns of the story, the wonderfully rounded characters and the Tardis crew are all in fine form in this story, and the reading by William Russell is, as always, absolutely spot on. This is 4 hours and 55 minutes of unalloyed joy to listen to, and is one that will be treasured and listened to often.