SPOILER WARNING: This article contains spoilers for this past Wednesday's episode of "Arrow," "Heir to the Demon."

When a show won't have a new episode for a few weeks, that last fresh installment tends to be fairly loaded -- which certainly was the case for this week's "Arrow," "Heir to the Demon."

With no new episode on The CW until Feb. 26's "Time of Death," "Heir to the Demon" was headlined by the debut of Ra's al Ghul's daughter, Nyssa al Ghul (Katrina Law). She arrived at Starling City not just to bring Sara Lance (Caity Lotz) back to the League of Assassins, but more importantly back to her, with the revelation that they once were in a romantic relationship. Sara and Oliver (Stephen Amell) are ultimately able to quell the League's threat, with the ordeal also revealing to the entire Lance family that Sara is indeed alive -- which is news that Laurel (Katie Cassidy doesn't take well.

The family drama spills over to the Queens, when Felicity (Emily Bett Rickards) finds out that Malcolm Merlyn (John Barrowman) is Thea's (Willa Holland) biological father, and subsequently tells Oliver -- who lets Moira (Susanna Thompson) know that he knows, and the fact that his mother kept that secret from him means that, beyond public appearances, they're no longer on speaking terms.

And it looks like Sara and Oliver are back together.

With clearly a lot to talk about, "Arrow" executive producers Andrew Kreisberg and Marc Guggenheim discussed the episode -- and future developments, like the debuts of the show's takes on long-running DC Comics teams "Birds of Prey" and "Suicide Squad" -- with reporters during a press event at The CW's Burbank headquarters.

On Nyssa and Sara's prior romantic relationship:

Andrew Kreisberg: It was really more about Sara than anything else. We didn't do it to be salacious; it's a pretty chaste relationship from what you see on screen. For us, it touched on a couple of interesting things -- the idea that Sara found herself in this terrible world, and found this one person who treated her with love and kindness. Even the way it bounced back for [Det.] Lance -- this hardened, tough cop, who's probably not the most progressive guy, even he was like, "I'm just glad you had somebody who loved you and took care of you during those nightmare years." Those little moments felt like they would be special, and play for us.

Marc Guggenheim: We actually specifically avoid using the term "bisexual." We didn't want to label [Sara] at all. Let her be her own person, and if the audience wants to label, fine, but we wanted to not make it that specific -- because it is a very specific relationship to Sara and Nyssa. Maybe Sara's had other female relationships in her past, but we'll get to that in due course, when it's right, if it's right. But we wanted to not just do something to shock.

On Sara's ability to stick around Starling City, now that the the threat of the League of Assassins has seemingly passed -- for now:

Kreisberg: This was not Katrina's only appearance of the season. Part of the reason we did this episode was to free Sara, at least for the time being, from the threat of the League of Assassins, and allow her to fully be the Black Canary, and come home, and all the delicious implications that brought. Part of the reason we did this story from the beginning was having this dead woman come back, and the effect it was going to have on everyone's lives. I think you got a glimpse of how some people are happy, and some people are very upset. In the next bunch of episodes, you're really going to see how Sara's return affects everybody. I think people will be surprised by the reaction.

On what's next for Moira after Oliver declares their relationship to be over, except for public purposes:

Kreisberg: If you've watched the series up until this point, you know that everything Moira has ever done, she has done to protect her family. It has sometimes been horrifying, and terrible, and borderline evil, but it's always been to protect her son and her daughter. For her arc this season, it's really about redemption. She went to jail, and kind of got away with it. She still hasn't really paid for what she did. I think if you see in this episode, she's paying off doctors, and she's threatening Felicity. She still really hasn't had her come-to-Jesus moment despite what you'd think would be rock bottom. And that's coming. This is a fractured relationship with Oliver that is not going to be mended in an episode. He's really mad, and this lie, as you could probably imagine from how it came out in episodes 7 and 8, it's going to have far-reaching implications for the characters of the show.

On how significant the disintegration of his relationship with his mother is to Oliver:

Kreisberg: It's huge. Oliver's one big, giant flaw is that he sees the best in people. Greg Berlanti's always said that Oliver has the exterior of a pessimist, but at heart he's an optimist. At heart, he really does see the good in people, and wants to see the good in people. I think that's why he's tried so hard with Helena, and why he's tried so hard with Sara, and why he's tried to reason with Slade. I think with his mother, despite all the terrible things that she's done, he can still logic his way through it. He can't see the evil in Sebastian, because he sees the good in him. But this time, he can't hide anymore. He can't pretend. He just can't pretend anymore that she's not a monster, and not a villain.

Will Thea find out the long-kept secret that Malcolm Merlyn is her real father?

Kreisberg: The cold war between Oliver and Moira is not going to go unnoticed by anyone.

Guggenheim: There's a great scene between Oliver and Thea about this territory in episode 17. There's so much in the Queen family that is impacted by the amount of lies. And not just Moira's lies. There's just lies all over the place in this whole family. Almost every episode post-this one really deals with the ramifications of all those lies. Can you have a family based on lies?

Kreisberg: And the irony of that scene is Oliver is saying, "All you are is your lies." All Oliver does is lie. I think that's part of one of the things he's going to realize -- as much as he despises his mother, he's actually a lot more like her than he wants to admit.

On whether or not, as Moira warned would happen, Oliver will resent Felicity for telling him the secret of Thea's parentage:

Kreisberg: It's actually going to be strengthened. She's the rock.

Guggenheim: I don't even think Moira necessarily believed what she was saying to Felicity. Moira was trying to manipulate Felicity into staying silent. It would never even occur to Oliver to be angry at Felicity. All Felicity is is the messenger here. I think his anger was properly directed at Moira.

On the long-awaited revelation of details from Felicity's backstory:

Kreisberg: There are two massive things that are going to happen towards the end of the season that you heard in that speech that will pay off.

On the "Heir to the Demon" scene that got cut:

Kreisberg: There was an amazing sequence in here that unfortunately we just had to cut for time, because this episode was so jam-packed. We actually had Oliver tell Roy (Colton Haynes), "I want you to go down to the hospital and keep an eye on Laurel." When Nyssa and her goon kidnapped Mrs. Lance, Roy confronts them, and Nyssa shoots him with a dart with snake venom, and she says, "A normal person would be dead by now, you're stronger than you look," and he says, "I get that a lot." Then they have a fight, but the venom starts to affect him and she takes him out. It was a great sequence, and they're great in it, but it wasn't propelling the story forward -- it was just a really neat moment. But the next five episodes really chart Oliver's attempts to keep Roy on the straight and narrow.

On the status of Sara and Oliver's relationship by the episode -- are they together, or, as a reporter at the press event put it, "vigilantes with benefits"?

Kreisberg: That's actually part of the journey of these next five episodes. Oliver has not had many successful relationships. He and Sara moving forward -- is this something that can work? "My last relationship was with an international assassin," and Oliver's last relationships were with the Huntress, and McKenna, who got shot.

Guggenheim: By the Huntress.

Kreisberg: And Laurel. That didn't work out so well.

On the "Arrow" team's growing comfort with episodes that put the focus on characters other than Oliver:

Kreisberg: I think that's been the benefit of getting to a season two -- you can start to move away a little bit. We announced that we're doing a "Birds of Prey" episode with the return of Helena Bertinelli (Jessica De Gouw). When we sit down, our first thing is always, "What's the Oliver of this episode? What is Oliver going through?" When we sat down and were talking about it, we realized very quickly, we realized, "You know what, this is a Laurel/Sara episode, and that's OK." We had that with [Diggle] (David Ramsey) in episode six -- it was really a Dig episode, it wasn't an Oliver episode. Success has allowed us to start looking at the other characters, and making their emotional journey the centerpoint of the episode.

More on that upcoming "Birds of Prey" episode:

Kreisberg: It's more the "Arrow" version of "Birds of Prey" than it is a direct adaptation.

Guggenheim: We gave ourselves room to grow and evolve that. The whole show is about evolutions -- it's about the evolution of the Arrow to the Green Arrow; we've talked about in terms of Black Canary and Deathstroke. The whole show is in terms of evolution. Birds of Prey is very much the same thing. You're not going to end up with the holy trinity of Oracle, Black Canary and Huntress right out of the gate. But the hope is, again, we're doing a multiyear, multiseason epic. We'll get there.

Kreisberg: Helena's gone. All that's left is the Huntress -- she's become consumed by this vengeance that she has for her father. It's the big final confrontation between she and her father, and Laurel gets caught in the crossfire. The Canary has to go into the rescue. It's a fun episode in that you get a lot of Laurel with the Canary, not realizing that it's Sara. The Canary is all too eager to kill the Huntress if it means protecting Laurel. It's really an episode about Sara realizing where she's at in her evolution as a hero.

On the next stretch of episodes, which Kreisberg jokingly referred to as "villains-a-go-go":

Kreisberg: Episodes 14-18 are just villain, villain, villain. Great big villains, one after the other. You're going to see a couple of returning favorites, and a couple of amazing, brand-new ones.

Including, as teased earlier in the season, the "Arrow" debut of the Suicide Squad:

Kreisberg: Episode 16 is called "Suicide Squad." And it's about the Suicide Squad. [Laughs] Dig was our way into Amanda Waller, and in this episode, Amanda comes to Dig and Lyla, and she basically recruits Dig for a mission, and basically tells him he's going to need a team -- and she saddles him with the Suicide Squad. Including Floyd Lawton [DC Comics' Deadshot, played on "Arrow" by Michael Rowe].

And, oh yeah, does the appearance of Nyssa increase the odds of seeing Ra's al Ghul?

Guggenheim: We really can't comment on when or if you'll see Ra's -- and how he'll pronounce his name.

Kreisberg: We've thought of the show as this multiyear, epic arc. Things get introduced, and get paid off later. This is one of those epic things that is being introduced now.