Spoiler warning: Do not read on unless you’ve seen the season three finale of “Orphan Black,” titled “History Yet to be Written.”

The season three finale of “Orphan Black” finally provided some answers for many of the show’s lingering mysteries — revealing the continued threat of Neolution and the survival of Susan Duncan, one of the scientists behind Project Leda and the creation of the clones. While the finale left Delphine (Évelyne Brochu) at death’s door, after a nightmare-inducing encounter with Dr. Nealon (Tom McCamus) and some kind of parasite, it also had its share of hopeful moments, allowing the sestras to share a sweet family dinner before Sarah (Tatiana Maslany) reunited with her daughter, Kira (Skyler Wexler).

Variety spoke to “Orphan Black” co-creator John Fawcett about season three’s twists and what he and fellow creator Graeme Manson have planned for season four, including a return to the “vibe of season one.”

First you killed Paul, then you shot Delphine — do you just hate happiness?

[Laughs.] I like happiness as much as the next person, but happiness sometimes isn’t as dramatic as tragic love stories.

Can you definitively confirm that Delphine is dead, or is there still hope?

I would love to say yes or no, but this is “Orphan Black” and I don’t want to say one way or the other … We wanted to leave it in a hanging cliffhanger, so is she dead? Is she alive? I want the audience asking those questions.

Aside from Delphine’s shooting, the season finale ended on an uncommonly hopeful note. Why did you want to go that route instead of ending with a cliffhanger this year?

It was really important for us in one of our most complex seasons to end with a lot of answers and feel like we’ve had some triumph and victory, and be in a place at the end of season three where we could go “now we can take a breather, we can reset.” We didn’t want to end the season in some giant cliffhanger that meant we were gonna have to start exactly where we left off. We wanted to feel resolution and have more of an emotional ending to season three, so that it gave us a chance to reset for the beginning of season four. We just wanted a very different feel.

On a related note, it’s been awesome to see Alison’s suburban subplot add some levity this season — how important was it for you to have that balance when the ongoing mythology has been so dark and complex?

One of the things that was fun about season three was the fact that Alison and Donnie became “Team Hendrix” and had their own storyline. It was a different way to approach Alison this season for us, and it was nice, just from a writing standpoint, having a clone character that we love have a very different story to tell that wasn’t necessarily linked to the main plot where everything has to be interwoven super intricately. It was nice to be able to use that as a breather and a little bit of lightness. Moving forward, most of the time, we’re using elements to set up things that we want to do, that we know are in our plan for season four and five, so that’s all I’ll say [about Alison’s storyline].

Was it always the plan to have the Neolutionists as the ultimate antagonist, or something you decided over the course of making the show?

When we put Neolution in season one, it was to pave the way for this later season. It was definitely part of the big picture. That was definitely premeditated.

What about Susan Duncan still being alive?

That was something that we always intended. That was part of the mystery of the past: the explosion in the lab, Dr. Leekie and the Duncans and young Rachel.

It’s been awesome to see Rachel’s trajectory this season — you’ve always been so adept at shading these layers of humanity into even the most villainous characters. What can you preview about her journey next season, now that she’s been reunited with her mother?

That one’s a very tough one to talk about, because those aspects of where she is and where that story is going is an important storyline for us that has a lot of bigger picture ramifications. The thing I can talk about, is that I just like the implications of putting young Charlotte under Rachel’s charge. Rachel has been a character we’ve set up as a clone who was very powerful in season one and two, had this desire to be a mother, and was angry about the fact that she couldn’t have children, and now has been damaged physically to the point where she can’t walk. She has a Neolution tech eyeball and has basically been given what she wanted, which was to be a mother, so from a character point-of-view there’s a nice, neat place to go. A lot of our thematic elements tend to revolve around motherhood, sisterhood and family, and family secrets, and those are the kinds of things that keep the show grounded in a place that people understand, that keep it working on a strong emotional level. Any kind of mystery about family secrets and digging into that — cause every family’s got ‘em -– I’m always really interested in those kinds of stories and those kinds of themes.

There’s been criticism from some viewers over the past couple of seasons that the show’s mythology is getting too convoluted, which I suppose depends on how much you appreciate serialized storytelling. Is that kind of critique something you pay attention to?

It always is — we don’t wanna confuse people but the deeper you go into a mystery, the more balls you’ve got to juggle. It’s a complicated story. I felt like it wasn’t that complicated, but I think the point of this conclusion, coming to the end of this season, was always to be able to go “okay, we got all these answers, so what’s next?” and leave the audience peeking into a brand new rabbit hole, and the nice thing about looking into a new rabbit hole is that you get a chance to begin again a little. There’s elements that I miss from season one too — Sarah not knowing, at all, what she’s facing or what any of this is about, and I think that’s a place we always intended to go at the beginning of season four.

How cognizant are you of the need to maintain the mystery but not withhold answers for too long? It seems like a lot of serialized shows have struggled with that ratio after “Lost,” where viewers become frustrated that mysteries are just piling on top of mysteries with no resolution in sight.

It was a real issue with “Lost” because it made people very grumpy, and it made me wonder whether the creators knew where the show was going or not. When Graeme and I first started on the show, it was like “let’s map out where we want to get to. What’s the endgame? What are the tentpoles for however many seasons we want to tell this story for?” And make sure that every step along the way, we’re giving enough answers. We may get more questions as we go, but we’re giving enough answers to the audience to keep them satisfied that they’re not just watching something that doesn’t have any conclusion.

I’ve always appreciated the fact that you don’t talk down to your audience. You assume a level of concentration and engagement in your viewers, rather than spoonfeeding them what they need to know.

When we were developing “Orphan Black” as a feature film, one of the movies that we loved was “Memento,” and “Memento” is not a movie that you can sit passively and be entertained by. I really got off on “Memento” because I was sitting there going “what the f—k is going on?” and you’re trying to figure it out, so you’re really working actively as a viewer. That’s the kind of show that we wanted to create with “Orphan Black,” that thing where you can enjoy it and it’s emotional, but we want to activate the viewer.

Krystal was an awesome addition this season — will we see more of her in season four?

Yeah, we really like Krystal and Krystal’s a character that we’ve obviously been talking a lot about, so she’s definitely someone that we like.

Every year, you push yourselves creatively and technically with a group clone scene. Last year’s clone dance party was obviously a lot more flashy, but the finale’s dinner scene must’ve been just as challenging in other ways.

In a lot of ways it was more complicated. With the dinner party, it certainly had a different set of challenges. It’s interesting because it’s not as flashy — even when I watched the finale again, I watch that scene and by the end of it, I realize, “wait a second, I just watched a big huge dinner with four girls around a table,” so it doesn’t really stand out as being bigger or better than season two, but it was important in the way we wanted to end season three. I just had this idea that our big clone finale was going to be a Last Supper kind of feel, everybody around a dinner table. It is about family, and Sarah has gone through this journey starting as irresponsible street urchin to mother, to sister, to matriarch in a way, and I think that where she’s at at the end of season three is a huge distance that character’s come since the beginning of season one. Somehow it’s just nice having everyone around the table and having an emotional speech from Alison.

The sequence took two days to shoot, and so all the actors — I think Kevin [Hanchard] who plays Art was only there for one day because I think he had a commitment on another day, so I shot around that. But all the other actors were there for two days and we basically did two clones per day, and did a lot of technodolly motion control angles moving around the table. It’s certainly a huge technical challenge for Tat because by the end of that scene… one of the things that I still laugh at, I cannot get enough of, is these weird improvised moments that happened right at the end of the take where they’re quizzing Helena about the baking that she brought. None of that was scripted, and it’s very weird to improvise with a character who’s not on screen. I had to start with Alison, so Alison started asking invisible Helena questions, and we didn’t shoot Helena until the next day, so everyone’s responding to this weird improvisation that went over two days and had to be pieced together. It’s still one of the funniest moments — I laugh every time I watch it.

What can you say about the theme or direction of season four?

I want from season four a vibe of season one again. I want a lot of that paranoia back, and Sarah following a first-person mystery, and a feeling of not knowing where we stand again, and having the audience not know where we stand. When Graeme and I talked about it, it was like, “how do we give it a feeling of conclusion after three seasons and now push towards our bigger mystery?” We just wanted a reset after season three and a big emotional ending.

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