It's interesting to talk about superhero movies because there's been a big change in the way these movies are built. One of the things that we're starting to see is that superhero movies, just like other big budget action movies, are actually being built more like TV Drama Series than they are like Feature Films.
Just like TV Dramas (and TV Comedies), rather than being built around a traditional character driven structure, these huge budget superhero and action movies are built around a concept called an engine.
In a TV Series, the engine is a kind of unique formula, developed by the writers, that guarantees that the series can run for a very long time, creating the same feeling in each episode in a slightly different way.
In these mega-budget franchises, the engine works similarly...