Baby Reindeer star Jessica Gunning: 'I couldn't stop thinking about the characters'

Jessica Gunning plays stalker Martha

Baby Reindeer, Netflix's latest word-of-mouth hit, has many people fascinated, disturbed and shocked.

The series is based on the true story of how Scottish comedian Richard Gadd was stalked by a woman after a brief, innocuous encounter in a London pub.

Warning: This article contains spoilers for Baby Reindeer and references to sexual assault.

The drama also depicts how Gadd was groomed and raped by an older man he considered a friend, and the harrowing impact on his life.

The actor wrote and stars in Baby Reindeer as himself, although he changed his character's name to Donny. Jessica Gunning plays Martha, the troubled fantasist who stalks him.

Gunning spoke to me about not seeing Martha as a "villain" and "feeling a responsibility" to her co-star.

Martha becomes a regular visitor to Donny's pub

We first meet Martha in the pub where Donny works, confidently telling him she is a high-flying lawyer who mixes with politicians and owns flats across London, but in same breath saying she can't afford a cup of tea.

Although Donny quickly realises she is a liar with severe problems, he is also drawn to her.

"I think Martha sees him in the way Donny wants to be seen, at a time in his life when he is so low, lonely and lost," Gunning says. "In a way, it was kind of perfect timing for her to come into his life."

But as Martha's stalking intensifies, Donny's life begins to unravel.

In one particularly strange scene, Martha says she wants to unzip Donny's body and climb inside him. She also leaves him a photo of herself in her underwear while inexplicably holding a bottle of Irn Bru.

Light and dark

I tell Gunning the inclusion of Irn Bru in a thirst trap was a funny moment in a show that is incredibly dark in parts.

Gunning says it was important for her not to play Martha as "mad" or "crazy" because she would lose the nuanced relationship between the two characters.

"I really cared about Martha, you know. As soon as I read episode one I was drawn in by her," she adds.

"I never saw her as a villain. I don't think you can do if you're playing that kind of part. I always saw her as multifaceted and complicated."

There is sympathy towards Martha too. Gunning believes her character is re-enacting "the life she should have had" instead of living her otherwise almost solitary existence.

Although Martha lies about being a successful lawyer, she does have a law degree - but was struck off for stalking a colleague.

Gunning says she "cared" about her character Martha

Gunning never met or researched Martha, and Gadd's real-life stalker has a different name.

She says she did not want to "muddy" things by knowing too much about her. It is an "interpretation", not an "impersonation", she adds.

The brutal honesty of Gadd's writing, which is almost confessional at times, is on display throughout Baby Reindeer.

What's even more striking is that he is essentially playing himself, reliving some of the worst moments of his life on screen.

An episode that depicts grooming, sexual assault and rape is especially harrowing.

Gunning tells me she "checked in" with Gadd "to make sure he was doing OK, especially during the filming of episode four - that was a really tough time".

She adds: "Richard was so amazingly brave and vulnerable and open to reliving all of that. I was so impressed with him."

The actress says some people who have watched the show have contacted Gadd, telling him how much the show saying they "feel seen" by his writing.

"You can't really ask for anything better than that can you?"

Gunning with Andrew Scott and Jodie Whittaker at the 2014 British Independent Film Awards

Gunning has been acting for 17 years, starring in the film Pride and BBC comedy The Outlaws, and jokes she has played 10 different police officers.

"I can do many a job," she laughs.

"But I feel Martha is kind of the role of a lifetime. I felt really moved by her, actually."

Gunning was aged with make-up to play the role, and Martha's Scottish accent is replaced in real life by her native West Yorkshire one.

I tell her that even though I know she is not Scottish I totally forgot while watching the series.

I ask if Baby Reindeer is a defining career moment for her. "I don't think of Baby Reindeer as a springboard for anything, or a moment. I just feel genuinely so proud to be part of it and I'm so proud that so many people are having such a response to it," she says.

"It's been so exciting. I'm so pleased that so many people are talking about it. I remember the day I got the script through for my first audition and I read all of the episodes in one go and I was just like, 'I think this might be the best thing I've ever read.'

"I always knew in my core that it was going to be a great show."

'Gruelling and compelling'

The series has been number one in the Netflix charts in both the UK and US over the past week and has a rare 100% rating on review site Rotten Tomatoes.

Variety magazine said the show is a "brilliant and jarring account of stalking, victimization and emotional turmoil", while the Telegraph called it "gruelling, if compelling TV".

The Guardian said the programme is "stressful and often distressing" adding that viewers should "come forewarned and expect to be rattled".

The immediate success has surprised Gunning.

"When I watched all the seven episodes, I thought this will be like a cult hit and, over a few weeks word of mouth will spread. So never, ever, did I think that within a week of it being out, it would have this kind of buzz.

"So I think both me and Richard are just 'whoa'. Especially Richard. I'm just so thrilled for him because he's been so brave and the response has just been incredible."

Baby Reindeer is not an easy watch, with both Donny and Martha getting into viewers' heads.

Gunning says starring in the show was a similarly intense experience. "Through the whole process she stayed with me. Martha and Donny," she says. "I couldn't stop thinking about them."

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