What is a Grandfather Paradox in The Umbrella Academy season 3?

Get ready for more time travel and super-powered characters because The Umbrella Academy season 3 is here! Picking up where we left off at the end of season 2, our favorite Hargreeves siblings are up against a brand-new threat when they finally arrive back home in their present-day — a new set of alternate timeline siblings called the Sparrow Academy. But that’s not all. Like previous seasons of the Netflix Original, the crew will have to face plenty of dangers in order to save the world again. But will they pull it off this time?

Spoilers ahead for The Umbrella Academy season 3.

Once the Umbrellas get acquainted with the Sparrows, they actually come together to take down something even bigger than sibling rivalry. The Umbrellas really messed things up when they time-jumped last, creating something called a Grandfather Paradox and in the process, a Kugelblitz. The world is starting to collapse into itself and timelines are being sucked up by this black hole, meaning the Umbrellas better act fast.

Of course, Number Five (Aidan Gallagher) is two steps ahead of everyone and as we saw in The Umbrella Academy season 3 trailer, he knows they accidentally created a paradox. Now, along with Lila Pitts (Ritu Arya), he must figure out how to fix it. And things get really trippy.

What does a Grandfather Paradox mean?

In The Umbrella Academy season 3, Klaus (Robert Sheehan) and Five discover that in this timeline, their mothers, along with the mothers of the other Umbrellas, all died on October 1, 1989 — the day they were born. This, of course, sounds crazy to everyone, but Five says it’s because they created a Grandfather Paradox when they time-jumped. What even is that? Well, the opening scene of episode 3, “Pocket Full of Lightning,” explains it.

According to the Commission, a Grandfather Paradox happens when someone goes back in time to change something, but accidentally goes back too far and changes the fact that they would even exist. The example they share in the opening scene of episode 3 sees a young man named Elmer going back in time to kill his grandfather so that he wouldn’t have to deal with him in his present-day. However, he went back too far to a time where he was not born yet, meaning there couldn’t be a way for Elmer to exist in his timeline.

The Umbrellas did exactly that, by accident of course, and now in their present-day timeline, they shouldn’t exist. Number Five and Lila time-jump to find answers as to how to fix the paradox, but they only have more questions once they meet an older version of Five who’s on his death bed.

Prepare yourself for more chaos this season, everyone! You can stream all 10 episodes of The Umbrella Academy season 3 right now on Netflix.