Agents of S.H.I.E.L.D. season 5 is essentially a mystery story. Coulson and his team have arrived in the aftermath of the world's destruction and must learn what terrible forces shattered the planet like an eggshell, so that they can go back in time and prevent the disaster from happening in the first place. There's just one problem: all records that might have explained how Earth was destroyed have been lost. The agents' sole guide has been Robin, the time-lost seer who experiences time out of sync. She's told Agent May how to save the world - but first, the team have to understand how it was destroyed in the first place.

So what can we say for certain? Little by little, Agents of S.H.I.E.L.D. season 5 has dropped some tantalizing hints.

Quake, Destroyer of Worlds

Daisy Johnson AKA Quake Destroyer of Worlds

Time and again, the series has described Daisy as "Quake, Destroyer of Worlds." At first, though, it was easy to doubt that Daisy was actually responsible for the end of the world. Deke, who grew up hearing the legends of the True Believers, managed to rebuild the Framework. He put the pieces together, and concluded that Daisy was the one who ravaged the Earth.

Deke is hardly an impartial source, though. His childhood had left the con-man bitter and frustrated, and he viewed the legends of the True Believers as a foolish superstition. It would certainly be fitting for him to dig into the few historical records that remain, and conclude that one of the True Believers' heroes was actually a monster. What's more, Deke was experiencing history by recreating the Framework. It's very possible he was experienced a twisted, distorted version of reality, in which Daisy had actually been a member of Hydra.

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Deke's views were apparently confirmed by Kasius. Although Kasius had done his level-best to erase all knowledge of Earth's history, he clearly believes Quake to be the "Destroyer of Worlds" as well. At the same time, Kasius is no scientist. He's driven by petty ambition, and wants Daisy as his prize. He hasn't stopped to consider the fact that time appears to be in a loop, with the twenty-first century and his present day feeding into one another. Matters of science, philosophy, and temporal physics are of no interest to the Kree aristocrat. It's doubtful that he cares much about history; the most likely reason he wiped out humanity's historical records was to try to end any movements that preached a message of hope. So, again, Kasius shouldn't be viewed as a reliable source.

Gravitonium is Back in Play

Gravitonium from Marvel's Agents of SHIELD

The next clue has been the return of a concept from Agents of S.H.I.E.L.D. season 1 - the fictional element known as gravitonium. In the episode 'Together or Not at All,' the S.H.I.E.L.D. team discovered that gravitonium was used to generate the Lighthouse's artificial gravity. Showrunner Jed Whedon has always promised that this concept would be revisited sooner or later, and it seems that now is the time.

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Fans immediately theorized that gravitonium was somehow involved in the Earth's destruction. That's apparently been confirmed in the last two episodes, which revealed that gravity is in flux around the shattered Earth. The surface is subject to devastating "gravity storms," random gravitational fluctuations that can be fatal to anyone caught up in them. Only gravitonium could possibly cause that kind of phenomenon.

Daisy doesn't have the power to destroy a planet. But if her powers interacted with gravitonium, anything could happen.

Quake Agents of SHIELD Season 5

The Last Day

The latest episode, 'The Last Day,' included an intriguing scene where Daisy headed out to confront an unknown threat. Whatever this threat was, it led the Government to evacuate an entire city. Daisy considered it so dangerous that, even knowing the likely aftermath, she chose to face it head-on. Given the involvement of gravitonium, it's possible that this threat was actually Dr. Franklin Hall, who was trapped inside a chunk of gravitonium back in season 1. Agents of S.H.I.E.L.D. repeatedly teased that Hall was still alive in there, and his emergence could easily be a global threat.

There are two important points to take from this. The first is that Daisy chose this. She knew the consequences if she acted; she was well aware that her actions that day would destroy the world. It's likely that she was dealing with a no-win scenario; that she believed the world would end without her intervention, and that this way humanity still had a chance.

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The second point, however, is that Daisy had interacted with Robin. She believed it was possible to save humanity, albeit difficult. She chose this knowing her actions would set up a chain of events that would save the world.

Exploring the Time Loop

Ultimately, everything hangs on Robin. 'The Last Day' explained the show's interpretation of time-travel. Robin has used her powers to create a time loop, in which the present and the future are linked together. It's important to note that Robin is no impartial observer. She is actively using her powers to reshape history, to find a way to save the Earth.

As such, it's no wonder Robin's mind is fractured. She isn't just experienced one reality; she's experienced countless. No doubt she was the one who found the Lighthouse, which became humanity's last refuge. She will also have been the one to guide Enoch to the Monolith, and it was her advice that led the True Believers to build the "isochronous cyclotron," the tech they used to control the Monolith from the future. Robin created this time loop in order to save the world.

Daisy destroyed the world knowing she was creating a timeline in which Robin would strive to rewrite history. She chose to use her powers, to crack the Earth like an eggshell, because she believed Robin would find a way to change it. It's possible the loop has run thousands of times, with each subtle variation bringing Robin closer to her goal. In one flashback, Fitz - who survived the Earth's destruction, along with Simmons - noted that the team had tried to rewrite history "thousands of times before." His studies had made him aware of the time loop, and of the recurring element to it. Fortunately, it seems that this time Robin has had the vision she most longed for. This, ultimately, is the loop in which she has finally seen a way to save the Earth.

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Little by little, Agents of S.H.I.E.L.D. season 5 has revealed how the Earth was destroyed. The team have a way home now, and it's up to them to travel back and see if they can't just avert this future. The time loop will have played out countless times before, whether in reality or in Robin's mind. Now, guided by the prophecies of the Seer, it's time for S.H.I.E.L.D. to do what they do best - and save the world.

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