Ella Purnell explains why Sweetpea is the most "nervous" she's been about a role

The six-part series stars the Fallout and Yellowjackets star as Rhiannon, a young woman who, after a lifetime of being ignored and undermined, is overcome by her repressed rage when her father falls ill and her school bully arrives back in town.

Unable to control her violent impulses, she embarks on a bloody murder spree that initially works to her advantage as she grows in confidence.

But her character transformation leaves some people scratching their heads – and determined to uncover the truth.

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"I put everything into this, I really did," added Purnell. "It was a tough shoot, physically. I worked every single day, long hours – night shoot, rain bars, covered in blood all the time, every day.

"And it's not a light topic. There's a lot of stress and crying and trauma. And to be in that place for six months – which is not a short shoot – of rage and so much anger, and getting into the mindset of a serial killer – it's not the funnest time.

"Well, it is fun. But it can be quite damaging to your mental health if you don't protect it. So it was challenging."

Purnell went on to say that she "definitely learned" more about herself through working on Sweetpea.

"That first kill Rhiannon has, she f**king loses it," she said. "She becomes an animal. There's something that snaps and comes out of her. I didn't know that I could do that. I didn't know if I was capable of that.

"And part of the reason why I wanted to do this job so badly, and why I care about it so much, is because I wanted to be challenged."

The actor also had to be careful not to "judge" Rhiannon, despite her being such a "morally complex, unlikable, borderline sociopathic character" – a role which was an entirely new experience for Purnell.

"All actors have this rule: don't judge your character," she added. "And I've never had to work so hard to not judge my character before. So the whole thing was a challenge from start to finish."

Sweetpea is available to watch from Thursday 10th October on Sky Atlantic and NOW.

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