[Editor's note: The following contains spoilers through the Season 1 finale of The Flight Attendant, "Arrivals and Departures."]

With its final episode of the season, The Flight Attendant brought to a close nearly all the major plot threads that have kept the titular Cassie (Kaley Cuoco) on the run. If you need a quick recap of the finale, here you go: with Cassie's casual-hook-up Buckley (Colin Woodell) revealed to be Feliks, who had killed Alex (Michiel Huisman) for the codes hidden in his paperback copy of Crime and Punishment, the danger is ever more real. Cassie and Megan (Rosie Perez) arrive in Rome, with the mysterious Miranda (Michelle Gomez) following behind — unfortunately for Miranda, she encounters Feliks before finding Cassie. Fortunately for Miranda, Cassie's managed to get a gun, shooting Feliks as he's poised to eliminate her... though it's Shane (Griffin Matthews), Cassie's fellow flight attendant, who ends up delivering the final shot that takes the assassin out.

Miranda manages to slip away, swiping some key pages from the Crime and Punishment paperback and leaving behind a note that she'll see Cassie soon. And more importantly, Shane not only reveals his identity as a CIA agent but there's a strong hint that it's a life that Cassie could find herself exploring as well — should the story continue.

And that, in the end, is the biggest unanswered question of The Flight Attendant: Will we ever get to see what happens to Cassie next? Executive producer Steve Yockey couldn't tell Collider for sure, when we spoke on the phone just before the finale premiered. But he did acknowledge the possibility, while also going into detail about the significance of Crime and Punishment to the story and whether we'd ever see Alex again in Cassie's "mind palace." He also reveals the recasting decision that was not caused by COVID, and the production decisions that were affected by the pandemic, and the inspiration behind the show's striking opening credits sequence.

Collider: Before getting into the finale, I would love to know a little bit about the opening credits — what was involved in creating them, and who was involved with the design?

STEVE YOCKEY: I had a really specific inspiration point that I wanted to go with. This is going to sound crazy, but there's this animated Japanese series called Cowboy Bebop that has animated credits that have this incredible jazz music. It's kind of a rock-jazz kind of track. I sent those as a sample, and also Blake Neely, the composer, and I had had a conversation — I was hoping that the music could feel like a Bernard Herman score for a Hitchcock movie, but if he was only allowed to use percussion. And so Blake's like, "So, I'm only allowed to use percussion instruments?" And I was like, "It's a challenge." And he was like, "Ha, ha, ha." But then he did that. And it's amazing.

So they had that theme and the Cowboy Bebop inspiration. And then we got on the phone with them and it was Warner Brothers actually did it. That's the same team I believe, or the same department, that did the opening credits for The Chilling Adventures of Sabrina, on Netflix. And they just went to town and when they came back their first pass on the animation was pretty close to what we have in the show. So, they were really getting the vibe and it all just kind of came together.

That's wonderful — I'm familiar with Cowboy Bebop and I love that that was an influence for you.

YOCKEY: Yeah. Those opening credits really stayed with me. And the only trick to it is — since you know them — I told them that they had to, like, fuck it up a little bit because Archer kind of already did the direct homage. That's already done. So we needed to do something a little different. I don't even know if Archer was doing an homage to Cowboy Bebop or just old kind of spy movies, but I love the way it came out.

Having watched the finale, and talking to you just after John le Carre passed away — I'd love to know, for you, how much of an influence was his work on the show in general?

YOCKEY: I think it's impossible to do a modern thriller and not be somewhat influenced, but I think probably the two largest influences, believe it or not that we had on the show were Alfred Hitchcock and Brian De Palma. I mean, Chris gave us mechanics to work with, you know for in the book and we veered from them in some places, but there was already kind of a roadmap. And then for us, it was much more about going on this sort of throwback stylistic journey to like a 1960s kind of thriller, and being informed by these directors, which probably isn't the best to answer since he just passed away. I should be like all of it, but like, I just...

It's an honest answer, which is honestly the best kind.

YOCKEY: Well, I appreciate that.

No, of course. I mean, it's also like you said, [Le Carre] is kind of embedded in all of this.

YOCKEY: I mean, it really feels like that. And honestly the show combined elements from several different genres to create this thing — I think there's just a lot going on in there.

Right. One technical thing I want to ask about is you had a big recasting situation where Sonoya Mizuno was originally set to play Miranda, but was recast with Michelle Gomez. What happened there?

YOCKEY: It's a pretty simple thing actually — as the later scripts came into focus, it became clear that we just wanted someone who was, I mean, quite frankly, more of a villain type. And so when we realized that, we made the change. I think everyone was copasetic with it. And we're very lucky that we found Michelle and that she was able to step in. Basically, she came on board between Episode 2 and Episode 3.

So this wasn't at all a COVID thing?

YOCKEY: No, I know that the timing of her announcement, the casting announcement, came out during sort of during that pandemic break that we all had to take. But that's a publicist timing type situation. We made that change very early.

Of course. COVID did end up affecting production on this season — what was the biggest change you feel happened from the original plan for the season versus what you were actually able to produce??

YOCKEY: I mean, honestly, we were lucky in that we had Bonnie Munoz, who's our DPM, along with our line producer, Ray Quinland, put together this safety plan that was above and beyond what anyone was sort of expecting us to do. We went further than I think we needed to but it works because we've avoided any mishaps. But because of that plan, we were able to execute pretty much everything that was in the scripts initially.

The biggest change was that a lot of our [outside] locations, we ended up having to build on a separate stage that HBO Max provided for us. So, like, we didn't go to a hospital. We didn't go to the jail cell. We didn't go to a lot of the places that we were going to go out to, just because of that's how we had been shooting the show up to that point was in real locations. But a lot of that got pulled onto stages where we had more control sort of over the human traffic. And then also the number of extras that we could use on the airplane set, in different locations — on different sets we had a max of 20 extras that we could bring.

So then it fell to our directors, who are Batan Silva and Marcos Siega for those last three episodes, to really kind of work with the DPs and their teams to make spaces feel full and alive in the way that they do in the earlier episodes. And the good news is when I watch the show now I don't see the COVID related changes. It's good that we could keep most of them off screen.

One of the toughest things for a lot of actors to pull off, I think, is the concept of acting drunk on screen. And I was curious from your perspective, what was the process of calibrating her performance, on your end, to capture that element of it? Because you have to make sure that's present.

YOCKEY: Yeah. I think in a lot of ways, the conversation that Kaley and I had, that was largely driven by her was, you know, Cassie is a functioning alcoholic. So in her life, a lot of times it seems like she's okay, even if she's just not quite yet at the next drink. And I do think that in the scenes where she has to play drunk, Kaley's really fantastic at giving you options so that you can figure out which one's going to work the best with the tenor of the scene.

It's not effortless because she puts a lot of effort into it — she's got a tremendous amount of skill. But she gives you four or five different versions, so you're really getting a feeling for and you can be like, "Okay, let's lean into this one." And then she just has it.

When it comes to structuring the series, you have a number of elements you're trying to balance — how much of it was set in stone from the beginning and how much of it you were you trying to figure out how to adapt, especially when it came to exploring certain twists?

YOCKEY: I think some of the twists came from the book and then some of the twists or things that we built into the series. All of the stuff about her childhood and all of the stuff that takes place in her head does not come from the book. So when we first sat down, when I sat down to pitch out the idea, I sort of had tentpoles or ideas of like, this is the episode where Cassie crashes a memorial service, and then kind of an idea of where the emotional tent poles fell. But when we got into the writers' room, that was when we did the work of really mapping everything.

How do you describe the sequences where Cassie is talking to Alex in her head?

YOCKEY: Oh, well, I mean we call it the mind palace, but I don't think that anyone would know to call it that unless they were in our writers' room.

So what came into balancing the mind palace sequences with all the other like actions happening? Especially because the mind palace sequences are so key to exploring the character of Cassie?

YOCKEY: I mean, when you read a book and you have to adapt it — the book The Flight Attendant by Chris Bohjalian is very internal. We spend a lot of time with her and to his credit, you really feel her anxiety and her guilt and her pathos and all of that. But, I mean, you can't watch someone feel guilty on TV, so you have to like figure out a way to get that on screen.

So for me, it was like kind of taking the scene of the crime, where she has this kind of traumatic experience of waking up next to this man with his throat slit, and then having that be the theme that she revisits over and over again, to try and figure out what happened, that's where she processes.

And then if you she's usually sent there in moments of choice or moments of anxiety, but yeah. And it just, it ended up working out so well, I think Michiel [Huisman] did a fantastic job of playing Alex, because his Alex was a constantly evolving character based on what Cassie was finding out in the real world about the real Alex. He would then incorporate that stuff into the way he was portraying the character. And I think it just worked out.

So, in the finale — first off, I want to ask about the book, because you plant Crime and Punishment in there. It's a big question mark in terms of what that means for Cassie's new journey — what do you feel like the book specifically indicates about what we could potentially see going forward?

YOCKEY: Well, I think the book is more a nod to what she goes through in the first season. I think when we get to the end of eight, she's sort of been on this journey where she's had to explore her own culpability and things and explore her own guilt and think, "it's not a murder." Often it ends up being like the death of her father, but she's had to kind of go through this journey of responsibility and acknowledgement and realize that, and come to these realizations about herself.

It's also super applicable to what we find Alex was going through. And so I think by the time she gets to the end, when she's walking through the mind palace, and each of the rooms are shutting off behind her, that when she sees the book there on the end and then the lights cut out before she can actually pick it up, I think she's sort of come to the end of the Alex Sokoloff portion of her life and that includes sort of wrestling with the Crime and Punishment aspect.

We always thought this would be a limited series, right? So if we get another one, that's great. And I know that Kaley's very excited. I'm very excited about the idea of [a Season 2], but I think it would be... I think it would be like another Cassie-bound-adventure. It would be sort of like, what's the next book?

Right. So Alex wouldn't necessarily be a part of her mind palace in a second season?

YOCKEY: No, I think the mind place would look different in a second season. It would be present because it's a part of our storytelling, but I think it would take a different form.

Right. I mean, and this is where the Le Carre influence. Not influence, but idea comes in because Le Carre was always about men and women getting drawn into the spy trade kind of by accident.

YOCKEY: Yeah. And I think, look, we set out to make a show where we gave a bunch of complex female characters the sort of roles that would normally go to men in a traditional thriller, and then let that play out. And I think that will continue. But I do like that idea. I mean, I have to say like, I'm a big fan of the idea of what is the next misadventure that Cassie gets drawn into.

Right. I mean, at the very least, like, it's probably a nice thing for you to spend the afternoon telling people like me whether or not you want to make more show after all this.

YOCKEY: I mean, honestly, like I am, I just think the show is so weird. And so many people had to take chances on it. Not least of which Kaley, she had total confidence that she could pull it off, but I went in there like pitching some weird shit. And so I'm thrilled with the response. I'm thrilled that people are seeing how amazing she is and, and that they're excited about the show. So that feels great.

Well, thank you so much for your time today. I really sincerely hope we get to one day talk about Season 2.

YOCKEY: Oh my gosh, I hope so too.

The Flight Attendant is streaming now on HBO Max.