"The end is coming."

That's what A.L.I.E. warns in the first trailer for The 100's fourth season. In the Season 3 finale, Clarke (Eliza Taylor) learned that the nuclear stations on Earth were melting down, meaning the planet would soon become almost completely uninhabitable. And in this first look at the new season, we see exactly what that will look like, as we're shown mass groups of people succumbing to the effects of the radiation.

But the trailer also shows Clarke, Raven (Lindsey Morgan) and the rest of our heroes fighting back and finding ways to overcome this dire situation. "If we stick together, we won't just survive. We'll thrive," Clarke preaches to her people.

Fans will be happy to see that Clarke has her right-hand man, Bellamy (Bob Morley), back after his turn to the bad side last season. But unfortunately, it appears as though Octavia (Marie Avgeropoulos) has sunk to her darkest place yet, earning the nickname Skyripper, aka "death from above."

Trouble also appears to be brewing between Monty (Christopher Larkin) and Clarke, and Roan (Zach McGowan) will return to do what his mother and Ontari never could: rule everything.

The 100 returns Wednesday, Feb. 1 at 9/8c on the CW.

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