The idea of happy endings will be explored throughout the upcoming sixth season of ABC's Once Upon a Time.

Season 6 of Once Upon a Time will bring things back to Earth, at least in Once's version of Earth. Storybrooke will be featured more prominently in the new season, in a way it hasn't been since the show's first two seasons.

All this and more was revealed at San Diego Comic-Con this year by series creators Edward Kitsis and Adam Horowitz. They spoke with TVOvermind at the convention, in a new article posted by the publication a few days ago, teasing major themes and special flashbacks.

"Can you really separate the good from the bad?" Kitsis teased, naming themes of season 6. "Are we really able to say that we're all one thing or another?" Another them includes, "What is happiness? What is a happy ending?" One aspect of this is the concept of whether happiness can be a lifestyle or merely "one final moment."

Kitsis spoke about how Storybrooke will be integrated into the main story more in season 6.

"The construction, the paradigm, even just back to the small town stories," Kitsis said, of bringing back that dynamic. "We're very excited to see Archie come back, and Leroy." Horowitz said that, "We wanted to be back in Storybrooke" to show how the other characters left behind are dealing with things while our heroes were away.

The show runners also teased the special flashback in the second episode of the season, which will center on the Count of Monte Cristo.

"Episode 2 we're going to see Count of Monte Cristo. It will have a tie-in to our beloved characters in the Enchanted Forest." Kitsis said, "You can't introduce Jekyll and Hyde and not tell that story." Horowitz added, "It's not all land of untold stories. There's a mix and match of different things we're doing."

Once Upon a Time season 6 premieres Sunday, Sept. 25 at 8 p.m. ET/PT on ABC.

Watch two previews of what's to come in season 6 of Once Upon a Time below:

Tags: Once Upon A Time television ABC