From auditioning for Andrew Lloyd Webber to playing the enigmatic lover of a suspected serial killer, via a Tom Hardy passion project and Tolstoy, Jessie Buckley's career has certainly kept us guessing.

Born in Killarney, Ireland, her first brush with fame was on the BBC's I'd Do Anything in 2008, competing for the role of Nancy in Oliver!. Last year she won our hearts as War & Peace's demure Marya and held her own against a flamboyant Hardy in Taboo, while on stage she's shone in The Winter's Tale and A Little Night Music.

This former talent show runner-up now finds herself leading lady of her latest project, Beast – her first film role and one that's more than a little daring. The feature debut of BAFTA-nominee Michael Pearce is set on Jersey amid a series of murders; it sees a young woman with a troubled past looking to escape the clutches of a suffocating mother (Geraldine James) by getting involved with Johnny Flynn's ominous outsider.

Beast is a remarkable and unsettling film. How did you come onboard?
I read 20 pages of the script and rang my agent straight back and said 'I love this, please get me into the room'; it moved me and challenged me, I felt afraid of it. There was a period where they said they might need someone who was more of a name, but I kept the script under my pillow and didn't give up. Finally they gave into my bolshie Irishness.

What about it excited you so much?
To read a female character like that. You rarely see anti-heroines. Moll is the kind of girl who ate worms in school. I thought I can do that, I'm better at playing those kind of female characters than people who wear pink nail varnish – that's much more scary for me.

It is still rare but slowly we're seeing more of these complex women onscreen …
Absolutely. It's such an exciting time. The kind of sheen that has been painted over women in film is slowly being taken away. You only have to look at what happened at the Golden Globes, people are asking questions about the boundaries that have been restricting and numbing us.

Beast is unusually accomplished for a first feature. Did Michael have a very clear idea of what he wanted, and what was he like to work with?
It was our first feature for both of us and we stepped into it terrified and exhilarated. We dared each other to go further and to jump off the edge of the cliff together. I think Michael is going to be one of Britain's great filmmakers; he's got a really unique vision and style, yet has a wealth of knowledge of the history of film. He's just the bloody loveliest guy as well.

Many will know your co-star Johnny Flynn from comedy series Lovesick but he's got form exploring his darker side, as we saw in Martin McDonagh's Hangmen …
He's been typecast as a psychopath and he's actually the nicest man in the world! We immediately felt we were in this together and trusted each other. Although it's a dark story, we were always excited to come in and play and explore.

I have to ask about Taboo. Will there be a second series?
I hope so. I spoke to Tom [Hardy] the other day. I said, 'Are we going back on the ship?' I haven't had a reply yet. Even if I have to swim to the bloody ship, I'll get on it!

Beast is screening as part of the Glasgow Film Festival 2018 and will be on general release from Fri 27 Apr.