We live in a time of split ends. Whenever a film franchise based on a book series approaches its final installment, a two-part conclusion is more or less a foregone conclusion.

This weekend, the first half of the conclusion to "The Hunger Games," "Mockingjay - Part 1," hit theaters. Plans to divide "Allegiant," the third book in Veronica Roth's "Divergent" series, became public knowledge before cameras starting rolling on the franchise's second installment.

How did this become the norm? You don't have to go back very far to find a very different movie culture.

To get an idea of just how different things were, you can look at the two biggest literary adaptations of a single year. Both "Lord of the Rings" and the "Harry Potter" movie series began in 2001 and do a sufficient job of showing how much things have changed.

"Lord of the Rings" and "Harry Potter" are really the properties that started the adaptation trends we see today, but it's the latter that shaped how conclusions are handled. Though both were among the first direct literary adaptations to go book-by-book in their translations for the screen, each handled their final installments differently.

Peter Jackson's "Return of the King" adaptation crammed as much of J.R.R. Tolkien's concluding chapter into 201 minutes as it could. "Deathly Hallows" opted to split, rather than cut scenes, which would have undoubtedly enraged fans and investors alike.

It's worth noting, though, that this wasn't always the plan for Harry, Ron and Hermione. When Steven Spielberg and DreamWorks were considering becoming financial partners with Warner Bros. on the boy wizard series, the legendary director proposed combining the events of two books into one animated feature, the opposite of what the franchise did in it's final chapter.

By the time, "Deathly Hallows" split in two, the movie-going public already had a small taste of the format. In 2003, Quentin Tarantino released the first half of "Kill Bill," which had debuted at Cannes as one, four-hour film.

Even before The Bride got her revenge, an adaptation of Charles Dickens' "Little Dorrit" starring Alec Guinness ran an impressive six hours. That film hit theaters in two installments, which opened at the same time.

Once "Deathly Hallows" introduced the concept of a divided finale, studios couldn't get enough. Since then, every major book series adaptation that has reached its finale has split it. Even Peter Jackson, whose "Lord of the Rings" now shines as an example of adaptation, has gone split crazy, dividing "The Hobbit" into three installments.

And the trend has grown beyond adaptations. For its Phase Three slate presentation, Marvel Studios proved that it was hip to the trend by dividing "Avengers: Infinity War."

So just remember, as the lights go down for the beginning of a film series' concluding chapter, don't get too misty-eyed. You'll probably be back in the same spot next year.