Credit: Eric McCandless/ ABC Family Photo: Pretty Little Liars Season 3 Finale: Spencer, Aria, and Hanna

The Pretty Little Liars Season 3 summer finale (Season 3, Episode 12: “The Lady Killer”) is only a day away and we are shaking with excitement over the big betrAyal. Wetpaint Entertainment sat down with producer Oliver Goldstick to discuss what we should expect in the finale, Haleb, and that sneaky CeCe.

Wetpaint Entertainment: You’ve created such a tangled web. How do you keep all the puzzle pieces together?
Oliver Goldstick: It's really a challenge. I hate to pull up the curtain and let the magician show his tricks, but if we had to be asked why certain decisions were made and had to be genuine, we’d say, “Because that person was no longer available. That's why we killed them. That person was killed because he got a feature, okay?” I hate to disappoint you. There was no ingenious plotting here. The person said, “Sorry. I'm going to go do a movie in Bulgaria or Vancouver.”

Do the big plot points ever change?
Oh, yeah. Some have. We've had to make certain adjustments just because honestly people's schedules sometimes didn't permit. But for the most part, nothing enormous because we have a game plan at the beginning of each season and know what our end game is. So we'll make requests for cast members ahead of time. But if they’re not under contract, you still are subject to whatever happens. An actor becomes unavailable, they're just not available.

You've set up so many people as potential suspects, and say someone like Jenna was “A” all long. Would that just be too easy? I would assume you're not painting yourself into a corner?
No. We try not to. There's two things going on. We want to pay allegiance to the books, obviously, to some degree. But when you have a show you want to run for four or five or six seasons, you have to keep introducing people. And the one buy just has to be “Why wasn't this person mentioned in season one?” Well, we'll have to write to that. What was the reason this character wasn't mentioned in the initial seven episodes when this person was a big part of Alison's life? At least, with Alison, we've created a character who was so secretive and so compartmentalized and so complicated for a teenager. Everyone has their own theories about her now, saying, “Wow this kid, this double life!” and to have all these encounters with adults and blackmailing parents - it's juicy and huge, but we have to look at it like it's an onion where you have to just keep peeling off layers. And some things make total sense because of a reference that was made 12 episodes or 20 episodes ago, and some things will have be like “In retrospect that would explain her behavior toward Toby,” for example. We have a revelation in episode 3‑18 where it’s like, “This explains why she felt this way, why Alison made Toby take the rap for an action that she was responsible for.” It maybe will be worked out later than it initially looked.

Do you guys just re-watch episodes over and over again?
We don't, because this group has not changed much. With the exception of a couple of folks, we’ve had the same core writing staff. And it's a small staff. It's really five of us since the day we started and we basically jog each others' memories if they’re starting to fade. There’s always someone in the room that goes, “Wait a minute.” Because there are things we discuss in the room that don't make it to the page, and then you think things are in the scripts that are not. So you have to go dig it out and look it up.

As far as Hanna and Caleb, is Wren a wrench in their relationship?
He has been, and I think that Wren, since he's not going away so quickly, will continue to upset the apple cart with the PLLs. And not just with Hanna and Caleb, but with the girls as well in the future episodes. He's kind of incorrigible, that Wren. He's not going to disappear. He stays on the scene and creates even more complications next season with a coupling that happens. But as far as with Hanna, right now, yeah, it's very confusing, because life would be much easier if you chose somebody that A would not target.

But wouldn't A just target Wren if he became important to her?
That's our logic here. But for Hanna it's a bit hard to get past the accent and all. Downton Grabby, that’s what we call him around the set.

And why has CeCe [Vanessa Drake] been brought into this universe?
Well, for multiple reasons. First of all, there's this whole thing in the books about, would you replace your friends if you got a cooler group of friends? This is sort of an ongoing paranoia and trope of high school, and the idea that she could actually befriend one of Jason's girlfriends, who’s become her mentor… We've always talked about Alison having a mentor. And it would be so wonderful if we found out, did Alison come up with all these things, or did someone have to coach her in all of her meretricious ways? Is there somebody in the background who taught her some of the manipulations, her methods or moves that Alison, obviously, perfected so quickly at age 15 and 16? We thought it would be great to give her an older friend and CeCe is one of those people where you have to keep questioning, what is she about? Do you think she's a genuine character?

I think she's one more person that we should be suspicious of.
Good. That's exactly what our intention was.

Are you going to start doling out some answers soon? Like Mona working with someone else?
You might know something about it in the finale. The finale you'll know something. How about that? You'll have some idea if Mona has a partner in crime by the finale.

And Alison's body, it's got to be so smelly by now? Where is it?
Oh, those bones, those rattling bones. Someone's made an instrument out of it, and they're playing it at Disney Hall this Thursday. No, Alison’s remains — believe it or not — they're going to come back into plain view, I should say, within a few episodes. In the imminent future the remains will be discovered.

Find more Pretty Little Liars spoilers here.

Catch the PLL Season 3 summer finale on Tuesday, August 28 at 8 p.m. ET/PT on ABC Family.

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