Avengers: Endgame's Most Confusing Plot Holes EXPLAINED

5. Forget Multiple Timelines, There Is Only One

It seems that every other website/author has a different take on precisely what the Avengers were doing across the film. Either every time they were delving into the past and doing anything, it created a splintered new timeline/reality, OR they were remixing the established MAIN timeline, and everything stays locked into one "core" progression.

Personally I think the latter makes the most sense, and it's backed up by comments from Bruce Banner and The Ancient One.

First up, during the scene where each character is mentioning the "rules of time travel" based on Hollywood's most popular examples (Back to the Future, Timecop, Terminator etc.), Banner wipes all these off the table, leading to them being called "bullsh*t". Where all these movies go down the route of "X thing changes in the past, therefore Y is affected in the present/future", Bruce states that the only perspective that matters is that of our characters.

Banner clarifies that "your past becomes your present", and as we're following THIS group of Avengers throughout, that's all that matters in understanding Endgame.

This is doubled down on by The Ancient One when Banner visits her, who shows us a visual diagram of the "main" timeline (highlighted in bright orange as a larger stream) holding together because all six infinity stones are present and correct. She notes that removing one to serve the present/future will fracture the core timeline, and reiterates the need for the stones to remain, so they can be used to defend Earth.

With both these pieces of evidence, it's safe to say that all the events we've seen across the last 21 movies are set in stone. You can travel back and pick up objects or characters to bring them forward, with the time in between essentially being Schrödinger's cat (existing and not existing simultaneously, until witnessed).

It's worth noting here that these black tendril "split realities" do start to exist (Loki escaping, for example), but the whole point of Endgame is to EVENTUALLY reduce everything back to one solid timeline.

At least, that's the only explanation I've found that works.

Onto the good stuff.