Marli Siu on why she relished breaking into boys' school as she joins cast of Alex Rider TV adaptation

It’s a series credited with encouraging teenage boys around the world to read.

The Alex Rider novels, about a 14-year-old MI6 spy, have sold more than 20 million copies in the past two decades.

Written by Foyle’s War creator Anthony Horowitz, the books were once described by former Education Secretary Alan Johnson as “the not-so-secret weapon” to get boys reading.

Now a new, big-budget TV adaptation has introduced a female character – and the rising star playing the role admits to being nervous about the reaction from long-time fans.

Marli Siu, who made her breakthrough in zombie musical Anna And The Apocalypse, plays school pupil Kyra. Kyra was created by screenwriter Guy Burt, who said it was “a condition of involvement for me, that we had a female character who could hold her own against Alex”.

Marli with with Otto Farrant in Alex Rider

He describes the character as a teenage version of Lisbeth Salander’s brilliant investigator from Girl With A Dragon Tattoo.

Marli, from Forres in Moray, said: “I’m a little wary of the fans asking why is she here, but I think the way it’s been adapted, a lot has been refreshed from the books and Kyra is part of that.”

The school where the series is set, the mysterious Point Blanc Academy, was all-boys in the book but on TV has girls on board, including Marli.

“I think it’s important it’s updated, because maybe more audiences will feel drawn into that world, and not just boys.

“I met Guy beforehand and he told me why he’d created her and where he saw her coming from, but I also had freedom to flesh it out myself.”

Filming the series gave Marli, who will also be seen in the highly-anticipated Our Ladies in cinemas later this year, the opportunity to film abroad for the first time.

“We filmed in Romania, up in the mountains,” she said. “We could only drive half way up, then we had to get into our costumes, eat breakfast, and then be taken to the top in snowmobiles.

“It was mad, quite an eye-opening experience. It was terrifying to feel like you could be stranded if the weather was to turn bad.”

Marli’s latest film, Run, was only five days into a cinema release when lockdown started.

“That was rubbish for the producers, but they managed to get it online and to DVD quickly,” she said. “I had been in the middle of a theatre workshop in London, where I live, when lockdown began.

“I’d been in the National Theatre’s The Ocean At The End Of The Lane, which was being transferred to the West End. We were working on changes to that, making some tweaks.

“I suppose I’m lucky I wasn’t in the middle of filming or had a theatre show cancelled.

“Since lockdown started, I’ve been reading and watching a lot of films, and I have a little balcony so I’ve been doing some gardening, which makes me feel like I’m outside.”

Marli was in Scotland just weeks before lockdown started, with both Run and Our Ladies receiving their red-carpet Scottish premieres at Glasgow Film Festival in late February.

“It’s so strange how quickly things changed,” added Marli. “Probably, if the government had acted a bit sooner, we should have gone into lockdown in February.”

All eight episodes of Alex Rider are streaming now on Amazon Prime

Sound and vision: Rising star on her favourite things

My boxset binge

Twin Peaks. I became obsessed with the first series years ago, got half way through the second and became so lost I gave up on it. But I really want to see the third series that David Lynch made a couple of years ago, so I’ve been making my way through the second series again. That’s taking up days of my time just now. Everyone should watch it – it will definitely keep them busy for a while!

A museum that inspired me

I prefer art galleries and I’ve visited the Tate here in London countless times, because there is always something new to find. I went to The Museum of Modern Art when I visited New York and it was the first time I saw a Francis Bacon painting in the flesh. I don’t know a lot about art but I like Bacon’s work (right), so that visit sticks in my head.

My favourite play

I saw Black Watch when I was really young, one of the first pieces of theatre I’d seen and it was incredible. I worked with its choreographer, Steven Hoggett, on The Ocean At The End Of The Lane, which was a bucket list moment for me. The way he added movement to Black Watch lifted it to a whole new level. That’s the cool thing about theatre – it shows you the magic, you see the cogs working.

Person I’d most like to go for a drink with

Probably my mum. She’s in Scotland. I think when you live with your parents, you take it for granted, so if you’ve gone home to isolate with your parents, just enjoy being around them. I would also love to go for a drink with my dad. He passed away a few years ago. Your parents are probably the most interesting people in your life, so have a drink with them if you can.

My favourite band or singer

I love The Kills – an ex-boyfriend, who was in a band, got me into them. I listen to their Midnight Boom album over and over again. But if I could sound like anyone, it would be Dusty Springfield. My mum used to listen to her a lot and when I think of my childhood, Dusty’s songs come to mind, with her incredible, effortless voice.

The first album I bought

I grew up in the Spotify age, so it was a lot of playlists I listened to, but as far as a hard copy, I remember buying American Idiot by Green Day. My best friend at primary school’s brother was into it, so I think that’s how it trickled down to us. I loved that album.

The most memorable film scene

The final scene in Shoplifters, a Japanese film, sticks with me. The father-figure character can’t say what he feels to the boy he’s been looking after, and as the boy gets on the bus, the man starts running after it. I cried, embarrassingly loudly, in the cinema. Any scenes showing humans unable to express themselves emotionally really get to me.

My ultimate dinner party guests

I recently read Just Kids by Patti Smith and she’s my new hero, one of the best people to have ever lived. She has so many stories and seems like the nicest woman alive, so 100% her. Also Steve Carell – he would be funny. I’ve thought about how awkward it would be to sit at the dinner table with strangers who you look up to, but I felt those two would be so nice in that situation. Also, Alexandria Ocasio-Cortez, who is in American politics, is quite young and really clever. I would want to sit and listen to her. Hopefully she’s a future president. And Kris Jenner, because she knows how to drink and party and I think she’s so funny. She’s an absolute boss.

The book I read over and over

My big sister used to read every night before bed and I got into that habit too, reading Harry Potter each evening. Another that sticks with me is The Lesser Bohemians by Eimear McBride, an Irish writer. It’s set in London and I read it when I first moved there. The way she writes is poetic, and it’s a book you can fall into and devour. I always go back to it when I don’t have another book to read at that moment.

My favourite actor

Carey Mulligan and Ben Mendelsohn are two who I’ll watch everything they’re in, as they seem to absorb whatever worlds they inhabit. I also love to watch Daniel Kaluuya and Jack Nicholson, because when they’re on screen you can’t blink as you don’t know what they’ll do next – they’re so exciting to watch.

A poem that changed me

I felt poetry at school could be long-winded and hard to access, but Ribs, a poem by Sam Sax from A Guide To Undressing Your Monsters, really made sense to me. For me, poetry is about the things you can’t say or don’t know how to say, but when you write it down in a poem it makes sense.