‘Avengers: Endgame’: Did Marvel Just Solve One of the Biggest Plot Holes With Thanos?

Movie fans like to go on about time travel “rules” so much, they’ve created a new rule: Every time someone makes a movie about time travel, someone’s going to find a plot hole. 

So it went with Avengers: Endgame, which had to resort to time travel to undo the massive damage wrought by the Thanos snap. (Yes, we know Spider-Man: Far From Home calls it “the blip,” but we think “snap” sounds better.) The movie uses time travel quite cleverly, doubling back on events from the original Avengers movie from 2012. Avengers: Endgame even references Back to the Future to try to establish its own set of rules.

Thanos fights Captain America
Thanos fights Captain America. | Marvel Studios

Nevertheless, fans still debate a plot hole — and that plot hole has supposedly been explained by the Russo Brothers.

What was the ‘Avengers: Endgame’ plot hole?

It goes like this: Past Thanos from 2014 views what happens to his future self when Thor cuts off his head. And, surprisingly, Thanos actually finds this amusing. He time travels to the present day after the snap with his very large army for a gargantuan battle with the Avengers. 

How does he do this, though, if only the Avengers had the Pym particles that make time travel possible? 

On the commentary for the Avengers: Endgame Blu-Ray, the Russo brothers note that past evil Nebula stole the Pym particles from present-day good Nebula. As the commentary track says: 

“There is a guy called Maw in his army, he was a great wizard. Thanos himself was a brilliant genius as well. Those two easily reverse-engineered and mass-produced Pym Particles.”

That would explain how Thanos was able to time travel it all, and it also conveniently explains how he was able to have a horde army of Chitauri with him. 

Or does it?

Time travel is very complicated in Hollywood

When people debate time travel logic in movies, they often use Back to the Future as the model, as that’s considered to be a time travel series with sound logic. The basic theory in those movies said that if you go back to the past and make a change, that alters your future. In fact, past changes can alter the future so severely that what you knew in the “present-day” becomes unrecognizable. 

In Back to the Future Part II, bad guy Biff in the future gets a book of sports scores. He time travels back to 1955 to give his younger self the book, so his younger self can place bets and get rich. The scheme is successful beyond old Biff’s wildest imagination, in that 1985 becomes a grim time when Biff rules over Hill Valley. Marty suggests going to 2015 to stop old Biff from stealing the time machine. Doc Brown counters that they can’t because the past has been altered, so the future is altered as well. 

Avengers: Endgame literally calls BS on this. 

‘Avengers: Endgame’ undoes ‘Back to the Future’ logic

When the Avengers decide to try time travel, Rhodey, not unreasonably, asks:  why can’t they go to the past and start from scratch by killing baby Thanos? 

The Avengers and friends have this exchange: 

Nebula: That’s not how it works!

Clint Barton: Well that’s what I heard.

Hulk: Who told you that?

James Rhodes: Star Trek, Terminator, Timecop, Time After Time…

Scott Lang: Quantum Leap?

James Rhodes: A Wrinkle in Time, Somewhere in Time…

Scott Lang: Hot Tub Time Machine?

James Rhodes: Hot Tub Time Machine, Bill & Ted’s Excellent Adventure, basically any movie that deals with time travel!

Scott Lang: Die Hard? No, that’s not one…

James Rhodes: Look, this is known!

Hulk: I don’t know why everyone believes that, but that isn’t true. Think about it. If you go into the past, that past becomes your future, and your former present becomes the past, which can’t now be changed by your new future!

Of course, the cynical among us could argue that’s just the movie’s way of saying: “There are no rules, so basically we can do anything we want.” Or as non-time traveler Indiana Jones put it: “I dunno, I’m making this up as I go.” 

In the end, it may be best to work with the old theory that the simplest explanation tends to be the correct one.  That’s either the Russos explanation or the idea that there are no rules, except that everyone will find plot holes in the rules. Fight us on that one, Hulk.