WARNING: The following contains spoilers for both parts of Batman: The Long Halloween, now available digitally and on Blu-ray and DVD.

While both parts of the animated adaptation of Batman: The Long Halloween certainly stay true to the original comic book story Jeph Loeb and Tim Sale crafted in 1996, the two-part film does take some creative liberties. The two-part animated film updates the story to reflect more modern sensibilities and to keep those familiar with the original story guessing. As the mystery around a serial killer stalking Gotham City on the holidays deepens, Batman: The Long Halloween reveals its own unique set of twists and turns. According to the film's screenwriter Tim Sheridan, these big changes were calculated decisions made by the production to both streamline the original story and keep audiences on their toes.

In an exclusive interview with CBR, Sheridan unpacked Batman: The Long Halloween's ending and explained why substantial changes were made for both films' major twists.

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You leave no illusions that Alberto isn't Holiday at the end of Part 1. He's straight-up fish bait by the end of the movie. Was that a nod to the audience that this isn't the story that they thought they were getting with that scene?

Tim Sheridan: It was so much more graphic in the script. they really pulled it back for the animation. I talked to people early on and everybody had a different idea about how the solution to this mystery works. Everybody I talked to had a completely different opinion and were convinced that they were right about what the solution is to The Long Halloween mystery. That was a big moment for us early on, we were like, "We're going to have to make some decisions and it's going to based upon our interpretation of how this story plays out."

Alberto Falcone, Batman, Selina Kyle - The Long Halloween

The Alberto thing was two-fold. One, we're streamlining the story so we can get to the resolution that we believe is the right solution; but, that was just our interpretation, just like every fan has their own interpretation of it. It also gave us an opportunity to surprise the fans who do know the book really well, which is why I was so graphic and explicit about it in the script. I wanted there to be no bones about it that Alberto is definitely gone. That was what lended to that. Ultimately, you have to make decisions about what you want to streamline and refine to get to the conclusion of the mystery. We felt that was a good opportunity to not only streamline but give a little surprise to folks who know the book so well.

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My big question about the ending of Part 2 is both parts has Bruce learn how to become the World's Greatest Detective over the course of the films, culminating in his conversation with Gilda whereas she gets away scot-free in the book. Was that change to pay off Bruce's arc?

There are great reasons why the book concludes the way that it does, but I think for us, in terms of telling the story for a movie, it's a Batman movie. You really want to feel that even if Batman doesn't full-out solve the mystery -- which is such an arguable point among fans about how the story plays out in both the book and the movie -- you still want him to be an active participant in the resolution. I felt like it was important to us to have that moment for them and for Batman to participate in it. It's important and also Batman gets to make a decision and we see him make a decision that may be good or may be bad, but he does what he does.

Gordon, Two-Face and Batman in Batman: The Long Halloween Part 2

Both parts of Batman: The Long Halloween are now available on digital HD, Blu-ray and DVD.

KEEP READING: Batman: The Long Halloween's Josh Duhamel Unveils Two-Face's Menace