Ella Purnell on "coming-of-rage" story Sweetpea and Fallout's "overwhelming" success

She was also the breakout star of the first season of Yellowjackets, about a group of New Jersey schoolgirls stranded in the Canadian wilderness.

But despite these transatlantic plaudits, the Los Angeles-based 28-year-old is actually a Londoner — and is back to acting in her own accent for the first time in years, in English drama Sweetpea.

At age 18, you were considering giving up acting to become a teacher. How relieved are you that you decided to stick with it?

Incredibly relieved. That being said, it’s still on the cards – I would love to teach one day. But it’s nice now, to have a bit more autonomy, a bit more creative control over what my characters looks like and the kind of roles that I want to do. I’m finally in the rooms I’ve worked so hard knocking on the doors of for the last 15 years.

Why did you decide to move to America — were the jobs on offer just that bit bigger and more exciting?

It was never really a strategic decision – it’s always about the parts, and I wasn’t getting the parts here.

Sweetpea is the first series you’ve acted in your own accent since Belgravia in 2020. Is that one less thing to think about in your performance?

It is. But I do feel very guilty about that accent thing. When I come home and I happen to use American words, I feel like I’m betraying my nation!

Filming Sweetpea, I occasionally found myself slipping into an American accent. It was a fantastic, humbling reminder to me that I was relying on autopilot in some elements of my acting. Which also says to me that I had perhaps forgotten some of my instincts. I needed to go back to basics.

The show is described, memorably, as a "coming-of-rage" story. What does that actually mean?

I always say, if you take away the murders, it’s a sweet story. My character Rhiannon was bullied as a child, and she’s never quite grown up. She made herself invisible to hide from her bullies, so never did the things other people do. She didn’t go on dates; doesn’t have any friends; has never been to a club. She starts to feel more empowered throughout the series.

She feels more empowered by killing her bullies and people who cross her.

How would you describe the tone?

It’s very firmly in the dark comedy world. It’s very British as well, which is another thing I love about it.

What does Sweetpea say about the life of a woman in the modern world?

It’s an inherently relatable thing for a woman to feel underestimated, undervalued. But it’s not necessarily gender-based at the start for Rhiannon. The key for me, getting into the serial killer element of her brain, was understanding that she’s not a psychopath. She has the capacity for empathy. I’m always looking for something different in a role.

Yellowjackets was a big departure from everything you had done before — did you watch your final scene in it?

With Yellowjackets, I’d never done anything quite so gritty – and can I tell you a secret? I’ve not watched the end, because it might freak me out. I’m not sure humans are supposed to watch themselves get eaten... While I was filming Fallout, I was getting all these selfies from the cast and crew of Yellowjackets with the model of my charred, mangled corpse.

It was a bit disconcerting.

There was a lot of early buzz around Fallout because of the huge fanbase for the videogame it’s based on. But the reaction surpassed all expectations — were you surprised?

We all killed ourselves for that job. It was a tough shoot, but it was worth it. And I don’t think I realised how well it was doing until I went back to LA after the show came out. People would stop me on the street and tell me how much they loved it. That was a new experience for me. Quite an overwhelming one.

When Fallout came out, you were back in the UK filming The Scurry — Craig Roberts's forthcoming comedy horror co-starring Rhys Ifans and Paapa Essiedu...

Yes, I can now afford to go and do a little British indie about killer squirrels in Wales for six weeks!

I left for Wales right after Fallout came out. There could have been no better time for me to hide from the world in the arse-end of Bridgend and do a really stupid but beautiful horror comedy.

And finally, Sweetpea’s Rhiannon has a kill list. Who would be on yours?

Ooh! Right now, the driver who took the mirror off the side of my car and didn’t leave me a note. Whoever that is!

Sweetpea airs on Thursday 3rd October at 9pm on Sky Atlantic and NOW.

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