Does Avengers: Endgame’s plan to defeat Thanos make any sense? We discuss.

The following story discusses major spoilers for Avengers: Endgame. Proceed at your own risk!

In the wake of Thanos’s snap at the end of Avengers: Infinity War, the Avengers had to resort to risky, drastic measures in Endgame to restore balance (and a bunch of their dusted peers) to the universe — and so did the film’s screenwriters.

Endgame revolves around the Avengers going time-traveling, back to specific moments in Marvel history — 2012 New York, 2013 Asgard, 2014 Morag, and 2014 Vormir — to obtain the Infinity Stones and assemble their own Infinity Gauntlet and undo the effects of Thanos’s snap.

The move allows Earth’s Mightiest Heroes and their legions of fans to revisit iconic moments from the 21 Marvel movies that precede Endgame, hitting a sweet spot between nostalgia and celebration. And in the process, the Avengers introduce touching wrinkles into Marvel Cinematic History, like a wistful meeting between Thor and his mother, and between Tony Stark and his father Howard.

But while Endgame is a love letter both to Marvel fans and to the studio’s expansive cinematic history, is it successful in its storytelling? Or, like so many other movies before it, does it become a deus ex machina cop-out?

Do Marvel zealots see flaws in the film’s logic? And if they do, should they care? Meanwhile, is its overall story compelling enough to convince more casual fans to just go along with the time travel?

Perhaps it’s somewhere in the middle?

Below, three Vox culture writers — who vary when it comes to how much they enjoy Avengers movies — discuss what they liked, what they didn’t like, and what they still have questions about after watching the Avengers go back to the past to save their future.

Alissa Wilkinson: Endgame’s time travel makes no sense, and that’s precisely why I love it

I am unironically delighted that Endgame is poised to drag America — nay, the world — into a pitched battle about how time travel, a thing humanity still can’t do, actually works. I love this stuff. I want diagrams and explainer videos and serious quantum physicists explaining how the Avengers resurrected half the Earth’s population with some shiny rocks they picked up in the past, before putting them back.

But let’s be clear: It makes no sense. At first, when the film’s quick explanation basically matched up with quantum mechanics — the idea that if you travel back in time, the past becomes your future, and then you close a kind of “time loop” — I shook my head and thought, Ah, okay, I can go with this.

And yet, as the movie goes on, the details start to unravel a bit. I’m unclear on whether the theory that the Ancient One puts forth (or, rather, illustrates with light in midair), about her reality splitting if the Time Stone gets moved, is in contrast to Endgame’s main time-travel theory, or if it’s specific to the Time Stone. I also lost track of how it makes sense for Captain America to make it to “our” timeline, in the present day, as an old person with another shield. (Did he do any superheroic things? Was he living in this reality alongside his unfrozen self, watching and knowing how everything would go down?)

But you know what? I don’t care. The fun of time travel in movies is that it is never quite consistent, never totally internally plausible, and that’s why we like to get our brains stuck inside them like gerbils on an exercise wheel. Even Endgame knows this, and throws a bunch of comedic shade at other movies that mess with viewers heads about time travel. That’s the fun part! It is, in the very best way, just a movie.

Allegra Frank: Endgame’s time travel makes no sense, but I love it anyway

There is something inherently unnerving about time travel. What will you find when you travel backward or forward to a place unknown? What if you disrupt the past as you knew it to be and completely alter your present? Can you erase your entire existence and return home only to discover that, uh, actually, you don’t have a home anymore, and technically never have had one in the first place?

Yet I am entranced by those who try to answer these questions, which I myself would never dare attempt to solve on my own. It’s why I absolutely love Back to the Future (Parts 1 and 2 only, natch); there is no right or wrong depiction of time travel in fiction, so go ahead and interpret it in the most fun, stupid, ridiculous, even upsetting ways possible, dangit. Why not throw Huey Lewis in there, and hoverboards, and a gratuitous musical number, and a weird relationship between our hero and his mom? (Maybe not that last one, actually.)

I’d classify Endgame’s time travel as “fun” and “ridiculous,” in that any troubling aspect of playing with the laws of time and space is mostly swept under the carpet. I love that Ant-Man insists upon enacting his ludicrous “time heist.” I love that everyone else goes along with it, after Tony Stark comes up with some nonsense that validates Ant-Man’s dumb theory. I love that Marvel mostly uses this plot device as an opportunity to revisit some of our favorite movies and settings for what is likely the last time.

So even though I have numerous qualms with Endgame’s time-travel plot on a philosophical level — including but not limited to: How many Steve Rogers are there now? How old are Peter Parker’s friends? What happens in the timelines where the past Avengers lost? And why weren’t they screwed over because of the present Avengers changing everything up, Tilda Swinton’s explanation be damned? How do I properly distinguish between the two anyway? — I can’t ding the time travel too much, because, hey! There’s no wrong. It’s all just a good time.

Alex Abad-Santos: Endgame’s time travel makes no sense, but stops short of going too far

The best thing about Endgame’s time travel is the way it lets Marvel’s biggest fans play along with the Avengers’ plan. Marvel fans are a devout group of humans, and when the team floats the idea that they have to find specific times in the history of the Marvel Cinematic Universe where they can find the Infinity Stones before Thanos does, I bet the most diehard fans knew exactly where to look and had already calculated the cinematic pockets of time the Avengers would be (re)visiting. That wouldn’t even be possible without Marvel’s extensive body of work and legions of fans who’ve watched every single movie multiple times.

However, when it comes to the question of whether or not Endgame’s time travel makes sense and is logically sound: No way. Steve Rogers sticking around in the past with Peggy Carter and marrying her becomes an extremely knotty thing when you consider that Peggy lamented in Winter Soldier she’d always held a torch for Steve. And then there’s the problem of Sharon Carter, Peggy’s great-niece and Steve’s love interest in Captain America: Civil War. I guess the explanation is that there are two Steve Rogers alive simultaneously in the current timeline, but that’s a little gross, right?

I have no clue.

Also, Steve is tasked with returning the Infinity Stones to their respective timelines. What happens when he returns the Soul Stone to Vormir, where Red Skull has become the Stone’s caretaker? How awkward is that? That’s an interaction I would enjoy seeing.

Ultimately, I think one of the reasons I’m okay with the less-than-bulletproof time-travel science of Endgame is that the movie doesn’t reset everything. The Avengers’ plan doesn’t take us back to before Thanos’s snap. There are unchangeable events like Natasha Romanoff’s death and Tony Stark’s death and Steve Rogers getting old. And by limiting itself by stating that changing events in the past doesn’t change the future but rather starts a new timeline, Endgame makes time travel feel consequential rather than a complete deus ex machina plot device.

But perhaps the bigger reason I’m okay with the time traveling is that I have a soft spot for Steve Rogers and I want him to be happy. And that’s how Endgame concludes. Congratulations on your happy ending, Cap, and thanks for all the memories (and the beard).