The Walking DeadSeason 8, Episode 1Andrew Lincoln as Rick Grimes, Lauren Cohan as Maggie GreeneÂOn "The Walking Dead," when one door closes, a window opens. This Sunday's finale will conclude the storylines of the eight seasons preceding it and pave a new path for the AMC drama in Season 9.

"This finale is about closure," showrunner Scott Gimple told The Wrap. "It's about closure of the All Out War storyline, but in some ways, this is a closure to the first eight seasons of the show."

He added, "Season 9 is going to be unlike things people have seen before on the show. And it really is going to take on a very, very different vibe — a very singular vibe unto itself."

The finale appears to be a final, conclusive showdown between Rick Grimes (Andrew Lincoln) and nemesis Negan (Jeffrey Dean Morgan). But what happens after that? This season already departed from Robert Kirkman's comic book storyline — Rick's son, Carl, isn't dead in them, as he is on the show. Will the show introduce the Whisperers, the next big bad in the comics, or veer into a completely unknown direction?

Gimple said the finale will "set the stage to start some very new stuff: very new challenges for the characters, very different kinds of stories, in different kinds of situations, a real evolution of the show."

He teased the upcoming storylines have "very very unusual and sort of new drives."

"People are going to see there's a lot more story to tell," Gimple promised.