Orphan Black” star Tatiana Maslany portrays multiple clones on BBC America’s cult favorite thriller. But while fans have gotten to know her many faces, there’s another integral visage viewers rarely get to see — that of Maslany’s acting double, Kathryn Alexandre, who has a front-row seat to Maslany’s dizzying process.

Below, Alexandre talks Variety through the complex and fascinating logistics of bringing the many clones of “Orphan Black” to life alongside Maslany.

Take us back to when you and Tatiana first met — how did you find the rhythm that’s become such a shorthand right at the start?

The first time I met her was at my third audition for the role of her double, so she was there and it was the first time we got to play together. I had prepared the scene that I was auditioning with and she played one of her characters and I would play the other, and then while I was acting I would just have to watch her and take in her performance and then we would flip and I’d have to mimic her. That was the first time that we met and we just got to feel each other out and were chatting a bit to got to know each other. Then, once I was in full consideration for the role, I went back to the studio and we did some shared tests — side by side tests to make sure that our skin tones matched and that kind of thing.

So we had a few chances to meet and to say hi and get a feel for each other before we were actually thrown into doing the scenes together. And then it’s just been constantly chatting and getting to know each other and I have really tuned in to how she moves and how she speaks to try and get a feel for her own rhythm and the rhythm of her characters, to try and mimic them as much as possible.

How did you get a handle on each of the clones?

It was mostly from watching [Tatiana]. I always wanted to just go from her perspective of the characters. Before we even started production on season one, when she was doing screen tests for the characters — because I didn’t know that much about them, I didn’t know how she was going to portray them — I asked to get the dailies sent to me so that I could watch everything that she did even in the screen tests to get a handle for how she was moving and how she was speaking and what they looked like.

I’ve continued to watch the dailies all three seasons that we’ve done every day, so that even when I’m not on set, I’m watching her work and I know how her characters move through the world, so I don’t have to ask as many questions when I get to set. So mostly just from watching and then sometimes I’ve picked her brain on certain images that she might be using for different characters, animal images, that dictate how they move through the world. If there’s a specific image she’s using, I’m curious what that is.

What’s the dynamic like between the two of you on set, in terms of how you approach the clone scenes?

My biggest concern is being there for her as an actor. So much of my job is very technical and I need to be so precise with the technical aspects, but I try to be as prepared as I possibly can so that when we go to filming the scenes, I’m not thinking about the technical aspects at all and I’m just playing the scene with her. That’s why I like to watch the dailies and watch her. She rehearses first and I watch her go through the blocking of the scene and I watch her prep for the character and then try to adopt her preparation. I often move through it almost as a dance before the cameras start rolling so that I get the movements in my body as choreography so that it becomes kind of autopilot once we get to the acting part of it. I can just listen and be a scene partner and be open to whatever happens in the moment, because she is quite dynamic and fluid and she changes take-to-take, so I need to be present and aware of what she’s giving me.

One of the most memorable scenes of the series to date – both performance and effects-wise — was the moment in which Helena saves Sarah in the bathroom in season two. What do you remember about filming that encounter?

It was quite an intense scene and I played Helena first. I kind of picked her brain about how Helena was going to move through that scene because it is such a unique circumstance. So she kind of ran through it a little bit and I tried to elaborate and pick up on what she had done and embody that for her, and yeah, it’s a very intimate and it’s very present and scary — it’s not for Helena, but it is both of those things for Sarah. So Helena, even though she just murdered someone, she’s there to protect her sister; her sister did try to kill her but she still feels this bond and she still wants to go and hug her and she just wants to feel that connection with her.

It’s terrifying for Sarah to see her come back from the dead like that but there’s such a want and such a yearning from Helena to connect with Sarah and almost to bring her down and to calm her. So it was neat as my role to embody that and try to give her as much comfort in that crazy situation as I could, and then when we flipped, it’s a little difficult because often when we flip, I don’t actually verbalize much for the technodolly scenes, so even though Sarah is screaming, I wasn’t actually verbalizing the screams. So it was an onus on me to give as much physically as I possibly could so that she could almost hear those screams even though they’re not coming out of me. So it’s really interesting technical aspects but I’m just always trying to pick up on little details that she does and give as much back to her and give as much emotion back to her as I possibly can.

Another fan-favorite scene that must’ve been even more technical was the “clone dance party” at the end of season two, which involved all four clones — what was the logistical process of filming that?

I think it was two or three days of filming, and there were two other doubles in as well that do what I do when we have more than two clones in a scene. We all had taped out squares on the floor in which we could move and we couldn’t override those boundaries at all. It was physically exhausting too, dancing that often, and I predominantly played Helena who was head-banging the entire time. I think I got a bit of whiplash after the first day actually. [Laughs.] It’s neat, even though these scenes are so big and they’re so crazy, they often feel very intimate as well though, even though you have the whole crew around you and a massive moving camera, and that’s probably a testament to how connected Tatiana is as actor. You feel like there’s nobody else in the room but the two of you or the four of you or however many clones there are.

Can you describe the process of shooting with the technodolly (a motion-controlled camera) and bringing those clone scenes to life?

Every day brings something new. Most of the scenes follow a general pattern but each have their own parameters that things change within. I prep the scene for however many characters there are, so either the two roles or three roles or four roles that we’re playing, same as Tatiana — we need to know all the lines and the story of each character, all of their different objectives and their wins and their losses.

So from an acting standpoint, there’s just a lot of preparatory work that goes into that before you even walk on to set and you have to be so much more prepared because you’re playing so many characters. A really integral part of the day is the first team rehearsal and the first time we run through the scene and we block it and Tatiana has the chance to walk through the different paths of her characters and I observe that. Sometimes we block it with her being one character and me being the other and if it’s a relatively simple scene, she’ll just say, “yeah, what Kathryn is what I’ll do, basically,” but sometimes it’s a little more detailed. So we’ll go through and shoot the scene once with her being one of the characters, and we tend to get a feel for it and make a floor plan for it in a sense, and then the technodolly — which is the computerized camera — we do those shots where after a while I’m taken out but she still has my voice in her ear with an earbud and she’s looking at marking tape on the wall.

Then once they’ve got that down, they throw me back in and do the over-the-shoulder, coverage shots. So even though we need to get one great take and stick with that blocking for the technodolly, there’s a lot of freedom in the coverage to play a bit more and delve a bit deeper and give her some new moments that she might find. Then we go off to hair and makeup and switch for an hour and then come back and do it all again, and we do that two or three or four times. So it is kind of like this double-dutch, skipping rope game where we’re constantly skipping between the technical stuff but also keeping it fresh and keeping it alive and really playing with the artistic acting of it, so it’s a fun balancing act.

Do you have a favorite clone to play?

It’s a little tough because I love them all and they all have their own challenges. Helena is a lot of fun to play because she’s so unexpected. There’s no other character like Helena. So you really need to shed everything of yourself and get really raw emotion because that’s kind of what she is — she’s almost like an open wound and she is so emotional and so animalistic and childlike and innocent but also has done all of these horrible things. There’s so many dynamics with her that every scene is really interesting to explore and could go in so many different ways, so that’s really exciting to play. And then I also like playing Alison and her storylines because she’s kind of the crazy mom in this little perfect suburban package, so that dichotomy is fun.

You got to appear onscreen last season as a character independent from the clones, Alexis, and have returned to that role in season three. How does it feel to get to act opposite Tatiana in a role where you’ll actually be seen?

It’s a lot of fun and I think it’s fun for the crew as well when we have those days. It’s kind of neat for the camera crew and they’ll be saying, “it’s nice to be looking at your face for once, Kathryn — we don’t have to hide you and you can use all of your arms and you can use your voice and you can have full access to every part of your body and we can film it!” So it’s a lot of fun to delve into that and it’s neat to have a different dynamic with Tatiana. She’s taught me a lot in terms of how detailed her acting is, because I’ve acted opposite her character so often. I’ve acted opposite Sarah as Helena; as Alison; as Cosima; as Rachel; et cetera, et cetera, so to act off Sarah as a new character, my own, that Sarah’s never met before, I just get a whole different character coming towards me from her. It’s really neat for me to watch her work and to feel that and feel all the changes and the detail in her work that, really without me having to do anything, she bumps you up a level because she’s just so talented and so generous of an actor and so fulfilled in her details.

Is your approach any different when preparing for a scene as Alexis versus one of the clones?

Not that much, because when we do a clones scene, I still do all the normal acting preparatory work that I would do as if I was on camera in the main scene. There is a slight change in how I prepare for that character in particular as opposed for preparing for Helena or Rachel, but in terms of the craft that goes into it, it’s all kind of the same. I think there’s maybe a little extra need for me to relax myself because you get that little bit of extra nerves when you know that you’re going to be in that final product. I’ve just got to calm myself down and be in the moment.

“Orphan Black” airs Saturdays at 9 p.m. on BBC America.