By 13, she was bored with acting. Then this young Kiwi found her spark

I never thought I was a very funny person,” says Thomasin McKenzie. Not that she minded. McKenzie, who is probably best known as the Jewish girl hiding in a cupboard in Jojo Rabbit, tends to be drawn to intensity, which is not a word you would ever associate with the spoof country-house murder mystery Fackham Hall. “But I learned in Fackham Hall that you don’t necessarily need to be super-quick or witty to do comedy,” she continues. She just played it straight. “And I think doing something that was so ridiculous helped me to loosen up a little bit. To luxuriate in the silliness of it, which really felt good.”

McKenzie and I are on different islands in New Zealand, Zooming across Cook Strait. At 25, she has already accumulated a startlingly varied body of work. She recently moved back to Wellington after two and half years in London, where her projects included working with Edgar Wright on Last Night in Soho with Anja Taylor-Joy. “I loved it,” she says. “But I was really missing home. And people are getting to the age where it’s time to be a bit more present, so I think I’m going to be sticking around for a while. I’m just so lucky to be where I’m from – why stay away?”

A generation ago, there was an obvious answer to that question, but Zoom is a great enabler; distance isn’t a disadvantage any more. “It’s funny. You’d think it would be,” she says. “I remember when I was much younger and having to do lots of American accent coaching, I used to wish I came from America. But when I signed with my agents, I asked them straight away if I would have to move to LA and they said no. If anything, it was interesting that I came from New Zealand.”

She is pleased when I say that her mastery of many accents doesn’t seem to have affected her own. You could cut it with a knife. “That’s good. Because I am a very proud Kiwi. I didn’t want to lose that sound.”

Fackham Hall finds McKenzie speaking posh cut-glass English as a bright young thing, a few years after World War I. Jim O’Hanlon’s film, written by comedian Jimmy Carr along with his brother Patrick and a team called The Dawson Brothers, is a mix of Downton Abbey, Cluedo and a saucy humour reminiscent of Carry On films. There are poo jokes and fart jokes, a parlour song – “I went to the Palace with my willy hanging out” – and a lot of jibes about the idiocy of the upper class; the family motto, inscribed over their stately home’s imposing gate, reads Incestus ad Infinitum.

McKenzie’s Rose is the second daughter of Lord and Lady Davenport (Damian Lewis and Katherine Waterston). A spirited filly who is staunchly resisting being married off to her oafish cousin – who, for reasons that are never clear and don’t especially matter, is heir to the estate – she falls head over heels for a young chancer from London, Eric (Ben Radcliffe).

Similarly lovestruck, Eric blags his way into a job at Fackham Hall as a footman. Love duly triumphs, and a murder and a Dickensian case of mistaken identity are thrown in for good measure. Mostly, says McKenzie, she is drawn to heavier subjects, but it turns out that her fresh, open face makes her an ideal ingenue.

Downton Abbey was the first television series that hooked young Thomasin’s attention. “Me and my dad watched it together. It was way back when you had to wait for each episode to drop each week. We loved it. I actually based Rose on Sybil from Downton.” She doesn’t think she’s broken faith with that fandom by spoofing it? “No, because it’s done out of love. It’s done with respect. I didn’t feel we were taking the piss out of it, because I think Downton is also aware of its own silliness.”

Both McKenzie’s parents are in the business; her mother, Dame Miranda Harcourt, is a well-known actor and acting coach in Wellington, while her father, Stuart McKenzie, is a director. Even so, she never imagined herself as an actor. “Because acting and being on set was so normal to me, I was pretty much over it when I was a child,” she once told Harper’s Bazaar. “My biggest dream was to work at a monkey sanctuary.”

She started acting to earn pocket money, but began taking it seriously when she played the victim of a real-life gang rape in a New Zealand television film, Consent. “I realised this could be a pretty viable career choice for me, because it gave me the chance to make an impact.” She was then 13.

She went on to make an international impact at the Cannes Film Festival in 2018 in Debra Granik’s remarkable Leave No Trace, playing the daughter of a traumatised Vietnam veteran (Ben Foster) living off-grid in the Oregon backwoods. Foster, who was then newly a father, told me at the time that he doubted an American actress could have been found to do the job. “I just feel there is a purity in her,” he said. “She’s very special. Her light is still on, she hasn’t blown her candle out and it’s a bright light.”

I’m reminded of that when I watch her being interviewed about Fackham Hall by Stephen Colbert on The Late Show in New York, saying frankly that she relies entirely on her stylist to dress her because she has no idea about clothes. I wonder if she ever feels under pressure to become a different kind of person, one more at home on red carpets?

“That’s a good question, because I definitely have felt that pressure,” she says. “A lot of people who aren’t in the film industry expect actors to be super-confident or to have a certain charisma. I’ve never been a particularly socially confident person. For a while, I really wished that I was, that I was more outspoken, more outgoing, that I could harness a room’s attention. Now I’ve just kind of leaned into my shyness; I realise it’s not how I am.”

The star-making industry is especially stressful, she says, for people who start young. “I know a few young actors who I try to be there for, just letting them know that being themselves is the best way to go about it.”

Since making Fackham Hall, she has again embraced intensity, playing a 17th-century Shaker convert in The Testament of Ann Lee, Mona Fastvold’s upcoming musical drama about a preacher regarded by her followers as the Second Coming. McKenzie plays Ann’s friend, Mary. She could hardly be more different from Rose.

“Every role I do, I seem to have a different approach for it,” says McKenzie. “Mary is obviously very much a woman of faith. My dad studied theology and my grandfather was an Anglican minister; my grandma is still around and attends church. So I channelled that, in a way. I thought a lot about my own faith and beliefs. But you have to be careful how much of yourself you put into a character. You don’t want to lose yourself. Hopefully, over the years, I’m finding that balance.”

Rose was easier, of course. “But it was still hard. Acting is hard. For me, I’m always questioning if I’m doing a good job or not. And making films is hard for everybody, from the producers to the runners. It’s a lot of work, so it has to be worth it.” There have been times when she has questioned that worth, certainly. “But no matter what you do, I think that question hovers over you: what is the point of it? And I definitely think acting has a purpose. Art has a purpose.” So she tries to worry less about being good enough. “Because I’m so lucky to be in this industry. I’m a very lucky person. And I want to embrace that, not worry it all away.”

Fackham Hall is in cinemas from February 19.

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