To understand the end of Calls, you have to understand the beginning of Calls. Which is to say, you have to understand "The End" of Calls. Got it?

The premiere episode of the new Apple TV+ series, Calls, ends with an apocalyptic moment in which the entire series rests on. It's gruesome, it's confusing, and it sounds incredibly unpleasant. (I mean, it's the end of times, what do you expect? Backstreet Boys?) But even in "The End," the thing that caused the end of the world on Calls isn't clear. But once you get to the end, it is. Again, got it?

Spoilers a plenty for the whole season of Calls follow.

Even though you may have been expecting aliens to show up for the curtain call on the show, as far as Calls goes, the end of the world is actually caused by a machine. But this isn't a Black Mirror-y twist, completely. Instead, it's a machine from a federal government espionage program from the '70s that kicked off the downfall of humankind. Robert Wheating, who was in charge of it, didn't even realize it was working.

What We Know:

• Robert Wheating was working as a scientist for the federal government in the late '70s
• Per his daughter, Rachel, "He led several espionages during the Cold War, all of them related to interdimensional communication"
• (So this doesn't have to do with aliens?) (But maybe Call of Duty?)
• His machine worked, unbeknownst to him, causing chaos from the past
• If the machine reaches its full potential — like in the first episode, "The End" — the first thing to go will be the gravitational field (check)
• Then everyone would float away (double check)
• Then there will be some type of aurora borealis (check, check, check)
• All things end in the blink of an eye

So no, Episode 8's Captain Perry isn't solely responsible for setting the end of the world in motion by landing the plane so he could get his daughter cookies. But he definitely didn't help it either.

As we learned in Episode 8, going against destiny disrupts the universe's integrity. By not preserving that integrity, the universe will eventually cave in on itself and everything living will be completely obliterated.

Throughout the series, we saw the universe course-correcting the actions of those that tried to change destiny, for example, Daisy in Episode 6. Daisy's mom called Daisy from the near future and told her that Daisy was going to die in a fire, so she skipped the camp where the fire was going to take place and decided to live her life to the fullest by attending a concert with some old friends. Well, then Daisy's face melted off and her limbs broke, and Nick Jonas' Sam was put in jail for most likely a very, very long time for her murder.

By Captain Perry not sacrificing those 350 lives in the plane for the sake of the universe, he created a much bigger ripple effect that eventually led to the events that happened in Episode 1. But if it weren't for the machine in the '70s, which allowed interdimensional communication to take place in the future, Perry wouldn't have had to make that decision. So, really the lesson is: Don't make the universe mad — you don't want to see it when it is mad.

Images: Apple TV+