None of this could have been in Hergé's mind when he began this story, which is again the first part of a longer tale spread over two albums. Even more so than the previous longer tales, this story is so unambiguously a first part that there isn't even a partial resolution of the events in this album. Was this always the plan or did the interruption lead to a rewrite of the ending so that it would not come to an initial conclusion too soon? There's nothing to indicate either way as there's been some minor polishing of the overall tale for the album, as well as a few anachronisms thrown in by the English translations coming out of order, such as references to encounters with Bianca Castafiore in stories yet to come or General Alcazar seemingly having previously met Captain Haddock when chronologically this is their first joint appearance. But overall this is probably the hardest of the all Adventures to review so far because it's not even pretending to be a story in its own right with a follow-up (in contrast to The Secret of the Unicorn), let alone a tale in its own right with a sequel (such as Cigars of the Pharaohs).
This is one contributing factor to what is the scariest and most fantastical Tintin adventure yet. A group of explorers have returned from an expedition to the Incas and one by one they are struck down by a mysterious illness that is triggered when a strange crystal ball is burst near them. During an evening with the final victim there is a storm and ball lightning first sweeps a seated Calculus into the air (as depicted on the cover) and then seemingly vaporises a mummified Inca ruler. Subsequently Tintin and the others have nightmares about the mummy coming to life and throwing crystal balls at them. Then on a daily basis the seven explorers all briefly awaken at exactly the same time and start screaming about figures attacking them. Although the rest of the story contains more traditional adventure fare of encounters in unusual settings, kidnappings and car chases, it's this fantastical element which makes the story stand out the most. Even the ball lightning sequence feels heavily out of this world. There's no explanation in this album as to whether all this really is magic or some great concoction. The implication is that the whole thing has been orchestrated by Chiquito, a rare descendant of the Incas who has been posing as the assistant in a knife-throwing stage act, but his potential involvement is only revealed towards the end of the album after he has disappeared. Seemingly uninvolved with the plotter is a music hall Indian clairvoyant who sees doom and the curse striking one of the expedition before it is announced.
The story doesn't even try to hide the influence of the legend of the curse of the pharaohs, with a train traveller in the first scene predicting doom and citing the case of the Egyptologists who discovered Tut-Ankh-Amen [sic]. At the time, there was a widespread belief in such curses and they had been taken up by Hollywood, although in actuality only a small number of the Tutankhamun expedition died within a decade, a not unusual rate. But whatever the realities or the explanation in the part to come, it's still daring to take such a trope and apply it to another culture altogether, though wisely the mummy coming to life is confined to a dream sequence. The morality of digging up tombs and taking the corpses is briefly addressed head on in the opening scene as the train traveller asks how we would react if people from other countries came to dig up our tombs, but there's no further discussion of the ethics here.
There's a brief bit of political commentary with the revelation that the music hall knife thrower "Ramon Zarate" is in fact General Alcazar, now deposed as military dictator of San Theodoros. The General is initially in exile after yet another revolution. This may have been a comment on the seemingly endless cycle of revolutions and military dictatorships in Latin America, but in showing a once powerful man reduced to such a job it may also have been a subtle swipe at the occupying Nazis. Whether a simple continuity error or a deliberate change because of the end of the war, at the end of the album Alcazar is heading home with no mention of having been restored to power, perhaps reflecting the changed world. There's some good comedy throughout the story, particularly with Captain Haddock's attempts to play the country gentlemen and instead going through monocles at an astounding rate, or the usual bungling by Thompson and Thomson as they get assigned to guard one of the expedition. Snowy is at times more a problem than an aide, chasing the Marlinspike Hall cat, howling down Bianca Castafiore's performance or getting drunk on heavily diluted whisky. Amidst all this Tintin shows even more detective skill than before, especially in the car chase when he rapidly discovers what the replacement car looks like.
Being only the first part of a two-part tale, it's inevitable that on its own this album doesn't answer all the questions it raises, which is an especial problem given how the story seems to be descending into fantasy and horror in a way not previously seen in the series. This also makes it hard to assess just how far the tomb curse trope really has been applied to the Incas. But the album is a strong, mysterious opener that builds up the mystery in an intriguing fashion, moves the characters into position for the conclusion and offers a good mix of adventure and comedy along the way.