Filming a regular, run of the mill episode of USA’s Mr. Robot is tricky enough on its own, mostly because there’s no such thing as a run of the mill episode of Mr. Robot. But for Carly Chaikin, who stars as Darlene, this week’s “404 Not Found” presented its own, particular challenge in the form of a one-take monologue filmed in the middle of a busy New York City street.

“…it would start raining, and then people would get into the shot, and then a cop stopped us in the middle of a scene,” Chaikin told Decider. “It was definitely one of those that was everything that could go wrong, was going wrong.”

Spoilers for the episode past this point, but in the hour, Darlene is trying to get a key piece of information to her brother Elliot (Rami Malek) over the phone, only he’s upstate trying to hide a dead body with Tyrell Wellick (Martin Wallström). Classic Christmas Eve scenario, right? To make matters worse, when Darlene figures out where Elliot is located, she gets mixed up with an extremely inebriated Santa played by guest star Jon Glaser. And when she agrees to take the Santa home in exchange for the use of his car, it turns out the man may be in worse mental shape than Darlene.

We talked to Chaikin about all of this, plus a little tease of what to expect as the final season of the series wraps up.

Decider: I wanted to talk about the incredible monologue you have at the beginning of the episode, where Darlene just goes from leaving a very simple “catching you up” message for Elliot, to screaming at him on the street. What was it like filming that scene, particularly because it’s all pretty much in one take?

Carly Chaikin: Yeah, that scene was kind of a nightmare to do. First we were on, we were in Chelsea somewhere, I can’t remember exactly what street, but it was a very public street. There was actually some sort of, I think it was Sleep No More going on in the building directly next to me, so I’m screaming at the top of my lungs, everybody in there can probably hear me. People were leaning outside of their windows from their apartments, watching, people were on the street just standing there watching, and then it was raining on and off so we kept having to start and stop. And then on top of it, I — you know, not to toot my own horn but I always know my lines, always, always, which is funny ‘cause, you know, every actor is supposed to; but we don’t always know our lines as well as we should.

But [showrunner] Sam [Esmail] will always say, “Carly knows her lines” — and that was the one time I hadn’t rehearsed it while moving around as much, like I’d always rehearsed and ran my lines just sitting there… When you actually are getting up and having to do all this other action, it totally changes the way your brain can access those lines. So for literally one of the most important things for me to actually be able to know those as well as I should, in the beginning I kept flubbing a line… That means you have to start over.

So it was a very hectic scene to shoot, and I kept being like “I’m sorry!” and then it would start raining, and then people would get into the shot, and then a cop stopped us in the middle of a scene… It was definitely one of those that was everything that could go wrong, was going wrong. But towards the end we definitely got it, and it was such a fun scene to do. It was hard, too, because I was very self-conscious screaming at the top of my lungs in front of everybody in New York, but it was definitely, for Darlene, a fun one to do.

And I imagine beyond that, you’re going through at least three to four spiraling emotions over the course of that one monologue, which probably makes things even more difficult at the same time.

Yeah, totally. When there’s a scene, especially a monologue, and you’re going through several beats, and kind of pivoting … It’s almost a two minute shot that’s one shot of just me, making it interesting to sit there and want to hear what I’m saying, and not having the use of camera and shots to make it interesting… It’s kind of just you. Granted, the camerawork in it is great in the way that they decided to follow me. But yeah, it was a lot.

The bulk of the episode, you’re working with Jon Glaser… Main important question I wanted to ask about this: what is your take on SantaCon? Because frankly, seeing a drunk Santa stumbling through the street right at the beginning of that just gave me total shivers.

[Laughs] Yeah, I mean, he was very very funny playing that, and the whole Santa thing is very bizarre. And I also, I’m Jewish, so I never went to the mall and sat on Santa’s lap, but I always wonder if kids actually think that each one of those is the real Santa.

Given that — I’m Jewish too — what was it like spending an entire season sitting in the middle of Christmas?

It was great! I mean, our world is more Christmas anyway, so it was like, the lights and all the decorations I have always enjoyed… It was just more of that.

Okay, back to Glaser… Your scenes with him are obviously very fraught as you’re riding in the car, almost the opposite of what you were talking about with that monologue; it’s really just the two of you in the car for the majority of the episode. How did you approach those scenes, and what was the vibe like on set?

Yeah, those scenes, that too, was a lot of being in my own head yet trying to engage, or not trying to engage [with] this whole idea where I think that he’s going to kill himself. And I mean, he’s obviously so fun to work with and very funny. Most of the driving car stuff was on our stage with moving backgrounds, which always kind of makes you a little carsick, but … I feel like with everything on this show there’s something special and interesting about it, especially as an actor, so it was just another good one.

I always think it’s very interesting as an acting challenge to approach something like this where the ultimate twist is, actually this guy is kind of okay despite all the that information we’ve been shown over the course of the episode. So you, Carly, as the actress approaching this, knowing this information, how did you get that out of your head? How did you push that aside, so you could approach the scenes as Darlene, in the moment?

There’s so many things going through this whole series where I forget that my character doesn’t know that, even though I know that, and so it’s actually very similar to when I watch the show with my fiancé. Even in the first episode this season when Dom is in her house and thinks that the Dark Army is in there, I know that it’s not and so I’m like, “Did you think that it was the Dark Army guy?” and he was like, “Well, yeah.”’ So it’s always so interesting seeing all this through the lens of knowing everything that’s happening.

All of TV and film and acting is suspending your belief, your actual knowledge of reality, and going into that character and taking it scene by scene, being in that moment and what’s happening right there, not what we find out later.

Obviously this is something you know the result of because you know the end of the season, but given where Darlene is in with her arc right now, she’s talking about how she’s lost absolutely everything except for her brother. Do you think at this point she thinks there’s any chance she could get a semblance of happiness back? Is there any sense she could get togetherness or community? And in a greater sense, is she able to repair the relationship with her brother at all?

I mean, at this point, there is kind of no hope. I think that she’s in a place of, “Literally, what would there even be to get back when mostly everybody is actually just dead?” And so I think that her only hope of salvation is her relationship with Elliot, which clearly is incredibly unreliable, unstable, and more or less horrible. But as we’ve seen throughout the other seasons, they do always find a way, one way or another, so I think that it doesn’t… It’s so hard to say without giving anything away later. But eventually she might see the light at the end of the tunnel.

Yeah, for me it was just another episode. … You know, one, I always forget what’s happening with everybody else and that’s one of the reasons why I actually enjoy watching it, because I basically black out what everybody else is doing.

Actually, the scene that I did where we get out of the car in front of [Jon Glaser’s character’s] house, was the first scene that I shot of the season. So that was really fun, too, being in March, the whole street covered in all those lights and decorations, and it being so beyond freezing I couldn’t feel my feet. But that fun fact, that was my first scene.

Before I let you go, how do you feel about how Darlene ends up on the show? Were you happy with her ending?

Yeah, I’m really happy with her journey, I have been from the start. I am satisfied and happy with how it ends, and couldn’t ask for more, basically.

This interview has been edited for clarity and length.

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