The Eternaut ending explained: What really caused the apocalypse?

It's soon revealed that this mysterious snowfall kills everyone it touches and technology suddenly stops working too, which means the survivors have a lot to figure out if they're to survive much longer.

That alone would be a lot to contend with, but when strange, bug-like creatures fall from the sky, it's revealed that this freaky weather was just the beginning. A full-blown alien attack is under way, affecting millions beyond Buenos Aires, where this show is set.

Based on Héctor G Oesterheld's Eisner Award-winning graphic novel, El Eternauta is a landmark work of the genre that Argentinian filmmakers have tried to adapt for decades.

With Netflix's version finally upon us, it's important to know that there's so much more going on in this story than these first six episodes let on. So, if you're ready for spoilers, here's what you need to know.

The Eternaut ending explained: Who or what really caused the apocalypse?

The first episode opened with Clara on a boat with friends when the blackout first hit Buenos Aires. We don't see her again until episode 5, when she suddenly shows up at Alfredo's home, which is where her parents, Juan and Elena, were holed up with their own friends.

Something's not adding up, though. How did Clara make it all the way back from the boat without any help? And why does she deny being on that boat in the first place?

Clara's being weird, and even has a freakout later in the mall, but she's not the only one. Rumours of people "going crazy" and attacking others start to come to the fore when Juan's friend Lucas vanishes overnight, right before three masked assailants start shooting everyone at the mall without a word.

Episode 5 ended with the surviving shooter walking back into the sewers where he passed through a group of alien bugs who didn't attack. In fact, they actually moved aside to let him pass, which suggests that he and the other shooters were being controlled by the aliens.

The Eternaut finale opens with Juan talking with one of the women who attacked just one episode prior. Together, they stand in front of a mural that happens to contain numerous elements that have already shown up or will soon show up on the show, including a beetle, a gas mark, a train and plenty more.

Juan has been having strange dreams or visions since the snow first fell, and he's not just losing it due to stress. Something much more important is happening here, but more on that later.

Collaborating with the military soldiers who rescued survivors from the mall, Juan, Alfredo and Lucas use a train to smash through the barrier and visit an abandoned building in the city centre. Their plan is to broadcast a message of hope throughout the area for anyone who's still left alive.

When the mission pays off, they spend the night in the building and enjoy a game of cards, just like they did at the beginning, when the snow first fell.

Except, this game ends badly too, in a very different way, when Lucas suddenly freaks out and stabs Omar in the stomach for no reason. Sure, no one liked Omar to start with, but he's proved himself since, and this is massively out of character for Lucas.

Juan chases their crazed friend up to the rooftop, where they find him rambling about tapped phones while he stands on the edge. There, the group also notice a huge blue light emanating from the stadium nearby. Lucas smiles briefly before his face turns blank and he suddenly steps off the roof to his death.

Juan and Alfredo have no time to mourn, however, or even figure out what happened, because a group of people with flashlights are suddenly spotted running towards the building. With Omar and another volunteer by their side, the group try to sneak out, afraid that the advancing mob are out to get them. Another volunteer shows up, but he betrays them all and calls out their location to the others.

Things get dicey, but everyone makes it back onto the train and escapes in one piece. But while the others head back to base, Juan decides to investigate what's going on at the stadium.

The train operator goes with him, and together they encounter a street full of people and the bugs walking around together. It looks like they have formed an army, all acting as one like they're being controlled somehow.

That's when we finally see the source of the light, and presumably who or what is controlling everyone. Well, we only see a silhouette, but it's clearly a new kind of alien creature, one who is controlling everyone with a gross, inhuman number of fingers.

In that moment, Juan finally realises why his daughter has been acting so strangely. The series then cuts to her practising shooting back at base camp with a very serious expression on her face.

Remember when her parents discovered a strange bump on Clara's head? This might be the method of control used by this alien to manipulate her and the others to do their bidding.

What could happen next?

With such a huge cliffhanger and plenty more story to tell, there's a strong chance that Netflix will renew The Eternaut for another season.

Speaking to Forbes, star Ricardo Darín recently said, "We still have the second part of The Eternaut ahead of us," which sounds promising. "I believe we're going to aim higher!"

If so, here's where the story can go next, assuming that it adheres closely to the source material. Prepare for some major spoilers from here on out.

In the graphic novel, the weird alien in question is known as The Hand, but it in turn is being controlled by other aliens who the protagonist simply refers to as "Them".

The next stage of their plan is to lure the army into a trap where they're destroyed by monsters known as "Gurbos". With some help, Juan blows up the dome and escapes just before a nuke is fired at Buenos Aires by international forces desperate to stop the aliens.

The invasion continues, however, as aliens continue luring survivors to "snow-free zones" they've set up as a trap. Eventually, Juan and his family manage to take control of a spaceship, but they're soon separated when he presses random buttons that hurl him into a pocket universe away from the others.

Over time, this "Eternaut" learns to travel between timelines and winds up in Buenos Aires a few years before the invasion begins.

Finally, Juan is reunited with his family in a stable time loop. That's why he keeps having these strange visions throughout the first season of Netflix's adaptation. Because he really has lived all this before.

These so-called visions of the future, as Juan suggests them to be in the finale, are actually memories of a future he's already lived through before.

The graphic novel ends with Juan deciding to write a comic about what's happened, bringing the story full circle in a delightfully meta way. That might be a bit too out there for this show, but let's hope enough seasons are commissioned to do the source material justice regardless.

The Eternaut is available to stream on Netflix now.

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