Rising star Emerald Fennell said she is a “greedy goblin” and wants to balance acting and directing.

Fennell is known for TV roles including the BBC’s period drama Call The Midwife as well as for playing Camilla Shand in season three of The Crown.

Behind the camera, the 34-year-old won plaudits for her work as executive producer on Killing Eve’s second season.

Her feature film directorial debut, Promising Young Woman, has just had its world premiere at the Sundance Film Festival, with initial reaction on social media overwhelmingly positive.

2020 Sundance Film Festival – “Promising Young Woman” Premiere
Carey Mulligan, left, Emerald Fennell, Bo Burnham and Alison Brie attend the premiere of Promising Young Woman at the Sundance Film Festival (Charles Sykes/Invision/AP)

Fennell said she is happy juggling both acting and directing for the forseeable future.

Speaking at the festival in Park City, Utah, she told the PA news agency: “It’s a funny thing. When I was little I just wanted to do anything. So, now I find I just want to keep doing it and keep working. It’s all so different.

“It’s nice to do those different things. It’s such an intense thing, it’s such a responsibility, directing and writing something. And you want everyone to have a great time as well as making something beautiful.

“And acting is incredibly difficult in a completely different way. You’re trusting someone else with that.

“I’m greedy. I’m a disgusting, greedy goblin, I want all of it.”

Promising Young Woman stars Carey Mulligan as a female traumatised by an incident in her past, leaving her to seek revenge against men who cross her path.

Fennell starting having discussions about the film with producers at Sundance two years ago and described the journey to get it made as an “amazing whirlwind”. She described Mulligan as “perfect” for the role but said it was not written with her in mind.

“I try not to think of people when I’m writing just because it can steer you in a direction,” she said.

“But Carey, once it was finished, Carey was top of my list. She’s just so exceptional. She’s so detailed and clever and funny. And I also wanted somebody who we hadn’t seen play a part like this.

“It requires somebody who can be completely a chameleon from scene to scene. And so she was just the perfect person.”

Fennell initially had doubts Oscar nominee Mulligan, 34, would take the role.

“I didn’t think she’d say yes,” she said. “I sent her the script and I met with her and thought ‘she’s just being nice’. And she sat down and said ‘look, I’m not supposed to do this but I’m in’. I just thought, ‘I love you, I love you, I love you’.”

Promising Young Woman is set to be released in April.