Brace yourselves, Oncers.

This Sunday's penultimate episode of Once Upon a Time marks the beginning of a "three-episode, all-killer, no-filler season-ender" and we know for a fact that heartbreak (and a hell of a lot of tears!) is headed our way.

To help get you prepared for all the twist and turns to come, ET called up Once's creators, Adam Horowitz and Eddy Kitsis, to get to the bottom of those dreaded death rumors, the "emotional roller coaster ride" ahead and what's to come in season six!



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Alright, guys -- let's cut to the chase: Is someone that we have fallen in love with for multiple seasons going to die in this Sunday's episode?



EK: Well, you know, it's hard to say who people have fallen in love with, but I can say that this weekend may break some hearts and a lot of people's questions will be answered.

If someone does die -- as your promo has promised -- what was the decision behind making that tough choice?



EK: Well, I can't comment on whether or not we're going to kill someone, but what I can tell you is our philosophy is we always do it to further the story. It is never taken lightly, it is never because of personal decisions, or this and that. These actors are our friends -- we love them. We love these characters, we love writing for them, but this show has stakes, and every once in a while, a death is used to further a character's arc or story -- be it for the good or the bad part of that person's emotional well-being.

AH: Going back to season one and the late, great Jamie Dornan, who was our first death on the show, no one loves Jamie more than me and Eddy -- except maybe Jamie's wife, but we're a close second -- and that was really difficult because that was always the plan. That was about the story and should someone pass away this season, it’s in that spirit. It's never easy, nor should it be. We take it very seriously. We know how attached fans get to the characters, and that really means a lot to us that fans get so passionate and so emotional about these characters -- and so do we. They're a part of us. We're writing and creating them, and telling their stories, so if and when we do let someone pass away, it's hard on us. It's hard on the writers, and it's hard on the cast and crew, but it's part of the storytelling process of a show like this.

What are the repercussions that this Sunday's episode is going to create before we see the epic two-hour finale?



EK: Oh man, it is going to be a grenade in the lives of all our characters… I'd say it's like the ying and the yang of life.

AH: There is potentially heartbreak coming this weekend, but I'll also say there's potentially hope. I think it's a mixed bag of emotions and, like Eddy said, it's kind of a grenade of emotions that go off and it runs the gamut of things.



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Which character's journey are you most excited for the fans to watch?



EK: This weekend I am excited for them to watch Zelena's journey, and for the finale, I'm excited for them to watch Regina's.

I understand that Regina is going to be in a very dark place in the finale. What can you say about that?



EK: I think what we're going to do is we're going to get a real quiet moment with Regina where she tells us how she's really felt about everything: her redemption, going good, being bad. What we're excited about is there is this really great scene where Regina lays her heart out there in a way that we've never really seen before. I don’t think we've ever really gotten into her head in the show and showed it like this before. People want to know what makes Regina tick and they're going to get it.

We've had some really great Zelena and Regina scenes, but we haven’t had many Regina and Robin scenes in a while. Are we going to see those over the next three episodes?



EK: Absolutely. We will see a bunch this weekend. I will say we'll find Robin and Regina in an old situation that may remind people of when they first met.

Maybe we'll finally get a little lion tattoo explanation?



AH: That tattoo is not going to be explained, but it's not forgotten either. It's something that you need to give us time on.



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I've had some serious Snow and Charming withdrawals over this entire season. Please tell me we're going to see more of them in these last three episodes?



AH: Oh yeah!

EK: There is a phenomenal scene between Snow and Regina that is one of my favorites and we are also going to see Snow and Charming in an adventure. They're going to be finding themselves in an old situation, but in a new place. I think we also missed Snow and Charming and we are really hoping next year to get more. I would like to see more of Snow White and Prince Charming and Bandit Snow and Swashbuckling Charming and I would like to just see so much more Snow next season.

I feel like we're due for another flash-forward. That always adds a fun twist to the show while we try to fill in the blanks. Is that something we could expect?



EK: You know, we've done it before in another show, so I wouldn't rule it out someday.

Have you already put thought into where our story will take us in season six as far as a new realm or a new land?



EK: I think season six is going to be different. I think every time the audience thinks they understand the show and how we work, we like to change it up, so this year's finale will not be an alternate reality. Next year will we see new realms? Yes, but we will be in Storybrooke. We will not be taking off in the premiere and going somewhere new.

I want a Storybrooke game night or karaoke party. Just something nice and drama-free for a change. Can we make that happen?



EK: Yeah! Personally, we would like to go back into those small town stories that we did in season one. There's a lot of Storybrooke yet to be mined and I think we're going to stay home for a while and see what happens.

What do you want to tell the fans before we embark on these last three episodes of season five?



AH: Well, first, thank you for watching this much. We hope you enjoy a bit of this emotional roller coaster and we hope that you find that amongst the heartbreak, there's also hope and also intrigue for what's to come next season.

Once Upon a Time airs Sundays at 8 p.m. ET/PT on ABC