[Warning: The following contains spoilers for Season 12, Episode 3 of Doctor Who, "Orphan 55." Read at your own risk!]

With one dark twist, Doctor Who delivered a timely warning about climate change on Sunday night. The drama's latest episode, "Orphan 55," seemed at first like your standard adventure gone wrong: The Doctor (Jodie Whittaker), Yaz (Mandip Gill), Ryan (Tosin Cole), and Graham (Bradley Walsh) zipped off to the so-called Tranquility Spa for a little R&R, only for the spa to be attacked by horrific monsters known as the Dregs. The spa was built in a bubble on the Dregs' home planet, an apocalyptic world called Orphan 55, in a greedy attempt to colonize land that should have been uninhabitable. But the barrier that kept the outside world at bay was failing, and the Dregs did not want company.

As the Doctor and fam raced to stay alive and save as many of the spa's guests as possible, the episode dropped a twist straight out of The Twilight Zone: Orphan 55 is Earth in the future. The Dregs are the mutated human race, evolved from the few who managed to survive. When the Doctor formed a telepathic connection with a Dreg, she saw flashes of disaster that looked like news footage: hurricanes, explosions, and chaos in the streets. This unlivable planet was the end result of climate change, which, according to the Doctor, led to the collapse of the food chain, mass migration, and war. "You had warnings from every scientist alive," she said.

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But while some tragedies on Doctor Who are fixed points, "Orphan 55" didn't go quite that bleak; the Doctor told her companions that the events they just lived through were just "one possible future" for the planet — one timeline. She ended with a desperate, very unsubtle plea to prevent that timeline from becoming ours.

"You want me to tell you that Earth's gonna be OK? 'Cause I can't," the Doctor said. "In your time humanity's busy arguing over the washing up while the house burns down. Unless people face facts and change, catastrophe is coming. But it's not decided. You know that. The future is not fixed; it depends on billions of decisions and actions and people stepping up. Humans — I think you forget how powerful you are. Lives change worlds. People can save planets or wreck them. That's the choice. Be the best of humanity."

And here we thought the Dregs' teeth would be the scariest thing about this episode.

Doctor Who airs Sundays at 8/7c on BBC America.

<p>Jodie Whittaker, <em>Doctor Who</em> </p>

Jodie Whittaker, Doctor Who

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