Consider also, though, that Tom Hiddleston’s Loki was initially meant to appear in the sequence, but was excised because audiences couldn’t grasp him as anything but a villain. “[I]n test screenings, audiences had overemphasized Loki’s role,” Hiddleston explained, “so they thought that because I was in it, I was controlling Ultron, and it was actually imbalancing people’s expectations. So Joss and Kevin were like, ‘Let’s cut it, because it’s confusing people.’” The studio was still learning how to make these films, yes, but the audience was learning how to watch them. Can you imagine those same people encountering something so sprawling as Infinity War?

Ultron is a mess, but the good news is that everyone seems to have learned from it. With Civil War and Infinity War, Joe and Anthony Russo have proven themselves to be efficient puzzle-assemblers, having coherently paired story beats with teasers and fan service. That could change, though. Endgame’s set to be the franchise’s most ambitious offering yet, with arcs to conclude, superheroes to resurrect, characters to fold in, and series to tease. They’re gonna need every second of those three-plus hours.