Who is the real Martha from 'Baby Reindeer'? Jessica Gunning says she didn't need to know

British actor Jessica Gunning said she usually has a "what will be, will be" attitude toward auditions. That, however, was not the case when she was trying out to play Martha in Netflix's surprise hit series "Baby Reindeer."

"I really kind of fought for it," she said in a video interview this week. "I really thought, if this gets into the wrong hands and it ever gets played by an actress who sees her as scary, or plays a kind of crazy version of a stalker, I think you'd absolutely ruin what is such nuanced, careful, delicate storytelling."

That storytelling was born out of creator and star Richard Gadd's real-life experience with stalking that began as a one-man stage show and was woven into a darkly comic miniseries about isolation and the aftereffects of abuse. In the show, Gadd plays Donny Dunn, a struggling comedian working as a bartender, who offers a cup of tea one day to Martha (Gunning), a crying woman. What begins with some mutual flattery eventually turns grim when Martha's affections turn to unrelenting harassment and threats.

But Gunning's performance never slides into mockery or horror-movie villainy. The Martha she creates can be frightening in her fury, yes, but she's also rooted in a deep sadness. Speaking from London, Gunning — whose credits include Prime Video and BBC's “The Outlaws” and the film "Pride" — explained how she tackled Martha and why she didn't ask Gadd for details about her real-life counterpart. This interview has been edited for length and clarity.

How did you start thinking about how you wanted to play Martha?

I think the way I always try and approach any sort of part I play is [to perform it] the most truthfully as possible. I would try and just imagine, I suppose, her home life and how she would take any small thing that Donny has said to her and just hold it so tightly. There's an amazing sequence at the end of the series where he's listening to all these voice messages from her. There's a bit where she says, "You were wearing a white T-shirt, and I thought in my head, you'd look so good in red, and then the next day you were wearing red." 

I think she felt like she was slightly magic with him. It's kind of an unconventional, unrequited love story from Martha's point of view, so that's the way I approached it. I never saw it as a kind of stalker-victim story. You can't ever play someone with bad intentions. I don't think she intended ever to be scary, even if she was received that way.

Did you think about mental health in playing her?

All of this story is told through Donny's point of view, so we're never with Martha's storyline in that aspect. But as an actor approaching a part like that, one of the themes in the show that runs through it, through many of the characters, is that of trauma. Obviously what happens to Donny in Episode 4 [which documents his sexual assault by an older man who was a mentor] is a huge part of how he responds to Martha and why he feels so connected to her when he first meets her, because she sees something in him that not many people have before. That's what bonds them together very quickly. I think that I would always try and connect any aspect of her to a kind of shared past trauma. I just think about how seen she would've felt as well by this guy. I mean, he even says himself in the voice-overs, he flirts with her, he compliments her, especially in those early episodes. She probably just felt so flattered and like they were properly in a relationship.

What was it like recording her voicemails? At the end of the series, Donny starts listening to them almost as he would a podcast or an album.

I prerecorded just for us the voicemails so we had them if ever [the production team] wanted to play them in the scene for Richard, just to add a little bit of texture to it instead of him imagining them. But then obviously, months later after everything is finished and cut together, you come back and do them in ADR [dialogue recorded in the studio after filming]. It was really an emotional time because the show had already been done. I hadn't seen Richard for probably about another six months because he'd been part of the edit with the directors and just very, very immersed in it. I think I'd filmed another show by then. I came back and then we did all of the ADR of the voice messages, but the last one we had together was that final voice message, and it never, ever failed to make me emotional. Even when I think about it, I just feel really, really emotional because it's the crux of the whole story really in a way. Both of us were crying. It was a really nice way to say goodbye to it and goodbye to the show.

What was the experience of filming the moment where Martha attacks Donny's girlfriend Teri, played by Nava Mau? 

They were really intense days and I was really concerned, obviously, that Nava always felt safe and protected. We had really amazing rehearsals beforehand with the fight coordinator just to make sure everything was put in place, so it was a dance almost and nothing came as a surprise. So that was really good in that sense because we had the chance to practice together quite a lot before we actually started filming.

Somebody said the other day, "Your body doesn't know what's pretend and what isn't, and it's so hard to get to that place." I used to always think when actors said that, I had a bit of an eye-rolly moment like, "Ugh, actors." But actually, it's so true. You do really feel like you've been through something quite traumatic because your body doesn't know otherwise. Also, all those days when we were filming Martha at the bus stop and Donny taking her back to her house, they're really emotional days and you can't help but feel affected by them. But hopefully we were all there for each other and we had a chance to check in after and had a bit of a breather, because as well as it being based on a true story it is obviously all us acting. It was a fine balance.

Did Richard ever talk to you about the person Martha is based on? 

He didn't really, no, and it was an active decision on both of our sides. I'm not doing an impersonation of her when we're doing this show. I'm doing my interpretation of this amazing character he's written, and I felt like it would muddy it too much because that's not what it is. It's all told through Donny's point of view, and it's based on a true story. I didn't find it helpful really to know too much about the person just because Martha is a character, so I'm doing my interpretation of her.

You mentioned this idea that your body doesn't know what's fake, so I was wondering what you did to shake off Martha once you went home for the night.

Throughout the whole job when I was filming, I was just obsessed with the story of it, so I didn't really shake Donny or Martha off until we finished filming. I was really lucky: My final scene was my final scene. It was the scene in the courtroom, and so that felt like a really lovely way to sum it all up because Richard had written this incredible stage direction just for the moment when she notices that Donny's watching the court case. It says that in the script, they lock eyes. This isn't a jump-scare moment or a success story. It's just two lost people looking at each other, and that is the kind of thing I take away from the whole of it. There's no winner at the end. They are just two lonely, lonely souls that had this crazy time together and this amazing story came out of it, but you're not left feeling that everything's tied up.

In that scene, did you think about Martha's future and what that might hold?

I didn't really think too consciously about that. In that scene, it was more, I suppose, her apology to him by admitting that she's guilty. It's her way of saying sorry. I think that's why I focused on it the most, which made me the most emotional. The fact that she doesn't say "not guilty." It's a big thing that she agrees that she did cause some harm with her actions, and that would've been really hard for her to have admitted.

What have you thought about the reactions to Martha as people watch the show? 

I haven't seen much because I'm not on social media, but I've been out and about in London and a few people have come up and just been great and very complimentary about the show in general. Often if they ask for a selfie, they make the joke, which is, "I won't ask for your number," and I'm like, "Oh, very good." I'm getting lots of lovely messages from friends saying, "sent from my iPhone," misspelled, which is very nice. I'm so glad it's captured so many people and people feel so moved by it, and people are just binge-watching it in one go, which I can't believe. I had to separate it when I watched it for the first time.

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This story originally appeared in Los Angeles Times.