A new clip from tonight's 100th episode of Agents of S.H.I.E.L.D. offers an explanation for what destroyed the Earth. Now in its fifth year, this may be the last season of Agents of S.H.I.E.L.D. But the minds behind the show are making sure to go out with a bang, as season 5 features perhaps the show's biggest plot yet. With the fate of the world literally hanging in the balance, the agents have returned through time and space to set things to rights, even as the government and the Kree are gunning for them.

We don't know how much of the story will come to a head tonight, but the 100th episode of Agents of S.H.I.E.L.D. will be both emotional and action-packed regardless. We'll see villains like Lash and Hive return, bringing with them all their complicated baggage. And then there's Coulson, who may be on the verge of dying for good this time. As for the impending destruction of the world, it seems we will get more clarity on that event.

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Marvel Entertainment has released an Agents of S.H.I.E.L.D. clip titled 'The Immense Forest' - named after the ecosystem in the basement of the Lighthouse - from tonight's episode, 'The Real Deal'. It seems that the three Monoliths kept in the base have been destroyed, which causes a tear in space and time. And according to Fitz, the result could be an entire dimension bleeding over.

Though Agents of S.H.I.E.L.D. has remained mostly disconnected from the MCU films, Marvel TV hasn't been afraid to introduce some major plots to the show. The Kree first appeared on the series before joining the films, and their presence has added a lot of extraterrestrial activity to the MCU. The agents have also dealt with time travel, dystopian futures, and alternate dimensions. What's more, all of those events are coalescing in season 5.

Along with Agents of S.H.I.E.L.D. being Marvel's best-reviewed show, the series has offered a lot for genre and comic book fans. Fantastical and sci-fi concepts regularly drive the plot, and the ensemble keeps things grounded with a mix of stellar performances and years of development. That should all add up to a rather intense 100th episode; not to mention a tense back half of the season, as it possibly heads towards a series finale.

After the shocking Yo-Yo twist last week, there's more than enough reason to believe heartbreak is around the corner for the characters and loyal audience. But as Agents of S.H.I.E.L.D. is never one to get mired in the doldrums, expect the heroes to rise to their latest challenges in some surprising and exciting ways.

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Agents of S.H.I.E.L.D. airs its 100th episode, 'The Real Deal', tonight at 9pm EST on ABC.

Source: Marvel Entertainment