Dublin Murders exclusive: Sarah Greene talks Cassie, Lexie and a possible season 2

Posted by
Lucy Robson
Sarah Greene as Cassie in BBC's Dublin Murders

Sarah Greene on playing Cassie (and Lexie) in Dublin Murders, as well as starring as Lorraine in the upcoming TV adaptation of Sally Rooney’s cult millennial bestseller, Normal People.

We are calling it: Sarah Greene is the woman of the moment. Not only is she currently playing two (very complex) characters, detective Cassie Maddox and her doppelgänger Lexie in the BBC’s Dublin Murders, her next role is as Lorraine (Connell’s mum) in Normal People, the eagerly awaited TV adaptation of Sally Rooney’s cult millennial novel, due out in 2020. 

But, like the rest of us, she thinks that she still doesn’t have everything together, as she starts our conversation berating herself about having a pay-as-you-go mobile. “I cleaned my room – I’ve been living out of suitcases. I live in London; I’ve been here six years and I still haven’t got myself an English phone.” Already we love her. 

Ahead of tonight’s Dublin Murders season one finale, Stylist spoke to Sarah Greene about her “gift of a role” in playing Cassie, following theories on Twitter, on being cast in Normal People (“I would have played a cat, if there was a cat to play”), and navigating young love. 

Rob and Cassie in Dublin Murders
Dublin Murders cast: Killian Scott and Sarah Greene as Detectives Rob Reilly and Cassie Maddox

We are huge fans of Dublin Murders in the office, so much so that we have a dedicated WhatsApp group set up specifically so we can discuss theories. There is A LOT going on isn’t there? 

It’s pretty confusing: you can miss so much when texting or even looking at your phone just once.

You have to stay focused to keep up, but then, I want to be challenged watching something, not drip fed, you know. Our brains aren’t equipped to focus that long anymore which is shocking.

It’s in the primetime BBC spot, so it’s a show everyone has been talking about. What attracted you to the story?

I read the script and I was just completely blown away by it. Sarah Phelps is so descriptive in her writing, it was like reading a novel. 

As soon as I finished the first episode, I couldn’t wait to get my hands on more, so I bought the books. Luckily The Likeness (the second novel in Tana French’s Dublin Murder Squad series) came in first, it’s like it was like a dear diary for Cassie, so it was the best research I could have been handed. It tells you so much about who she is as a person and how she reacts. Like having a bible of Cassie. 

What was the audition process like?

It was a funny process. After auditioning, I went away and was told I didn’t get it and I was heartbroken.

In my gut, I just really felt like, this is my part, I’m supposed to do this job, so I couldn’t really let it go. Usually, after an audition I’m grand and I don’t think about it again till I hear, but I couldn’t get this out of my head. When I was on holiday for my birthday, I was constantly refreshing IMDB to see who got the part. I couldn’t shake it off.

Then a week later after I got home, I got a call to say you’re back in. Which I was thrilled about.

Cassie is a really fascinating character, with a lot going on under her cool, calm exterior. What was it like to play such a nuanced, complicated character?

I got to play two characters (Cassie and Lexie) which was exciting. A gift of a role. You don’t get roles like that a lot.

I only had a short amount of time between finding out I had gotten the role before we started filming. I then spent the first two weeks with Killian (Scott) and Saul Dibb, the director, sitting around a table, working around who these people are and how we wanted to play them.

Then we were reading only the script for the next two episodes at a time – so we were as much in the dark filming as you are watching. We weren’t sure what was happening.

The very first scene when Rob and Cassie have an intense conversation (set four months later), I called Sarah and was like, “what happened, why aren’t we going to see each other again?” So They gave me a little bit of a clue but not really, which was really exciting - because you can’t play history and you can’t play the future, you can only play the moment. But to have all the underlying detail to a character, it was pretty epic. It definitely wasn’t boring.

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It’s quite different to the other police dramas on TV at the moment, like Line of Duty and The Capture

Yeah, very different to your usual police dramas. It’s not a procedural, it’s more about the characters’ back stories – who they are as people, what happens when their pasts catch up with them – more than solving the case. So you are invested in them as people, rather than just watching them do their job.

It’s more like a gothic fairytale, which I don’t think you could tell from the initial trailer or even the first episode. I actually got into a deep worm hole on ‘the fetch’ (a supernatural double) in Irish folklore earlier today, its fascinating (but also completely terrifying).

Sarah Phelps really wanted to bring the Irish folklore into the show, with superstitions and rituals running through it. It’s true to Tana French’s books as well. Especially in the second book (The Likeness), which is about being about a doppelgänger, and what it means if you meet your doppelgänger face to face, does the world end, as the mythology says?

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I read that Sarah Phelps was influenced by a real-life incident where a man protested against a particular tree being cut down, as the fates would be disturbed  a protest he then won. It’s like, on some deep, conscious or subconscious level we have this niggling feeling, what if?

Yeah, don’t disturb the dragons or the demons. Lexie was born as a coping mechanism when her parents died in the car crash, as her alter ego. She is the darker side of her, who Cassie battles her whole life. 

And now Lexie is real?

Well she’s someone who looks exactly like her – and it’s quite easy to look like someone.

When Cassie was pulled out from being undercover (as Lexie), the rumour was that she went to rehab, so this girl, whoever she was, is like “it’s me, i’m back” and stole her identity. If you stay silent and let people talk to you, you can piece together who someone is, and pretend to be them, if you’re clever enough. 

There are a lot of theories out there on social media. Have you been following those? 

I did check Twitter the other night because my sister told me to have a look, as i’ve been trying to avoid it. It’s just a gas because everyone is so confused!

One I saw was, “Cassie is actually Jamie,” which is funny because Ellie (O’Halloran), who plays Jamie actually played my daughter in Rosie, so we do look similar.

I also read a funny tweet from someone saying “it’s like eating a block of cheese before bed and having really bad nightmares.”

Dublin Murders: Sarah Greene as mysterious Cassie lookalike, Lexie

Did you expect Dublin Murders to be as successful as it has been?

You try not to think about that. You hope a show is going to go down well, you hope people are going to enjoy it, but you try and put that out of your mind when you are shooting as that can be a bit daunting. It’s unneeded pressure that doesn’t benefit you in any way.

But I’m so happy people are loving it and trying to figure it out, as everyone has poured their heart and soul into it.

In the Dublin Murder Squad book series - each novel is narrated by a new detective each time that’s closely connected with the crime, and one of the previous detectives is involved. Will Cassie be returning?

Cassie isn’t in the next book, so I don’t know. Hopefully, I’d love to go back as we had such an amazing time filming. The crew in Belfast just came off Game Of Thrones, so everyone is at the top of their game and really really skilled. I also love Belfast; it’s a buzzing buzzing city – I spent seven months up there filming.

I would adore the chance to go back – but ask Sarah Phelps, it’s up to her!

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Dublin Murders Frank and Cassie
Dublin Murders: detectives Frank and Cassie try to solve the mystery of Lexie

Your next project is Normal People, the eagerly anticipated TV adaptation of one of the biggest and most-loved books of the year. How does it feel to be involved?

I’m really excited about it. I think it’s going to be really special!

Our two leads (Daisy Edgar-Jones and Paul Mescal, who play Marianne and Connell) are just unbelievable, I can’t wait for the world to see them. They are two of the most beautiful people I have ever met in my life. They play those parts in a way thats so beyond their years, and they got on so well themselves. It would have been a disaster if they didn’t get on.

They are just the best of friends. And they are just incredible actors and gorgeous people and I just want the world for them because they completely deserve it.

Also, the writing is so beautiful, and Lenny Abrahamson (the director) is someone I have wanted to work with forever. I was so happy to be cast as Lorraine, I love the character. But I would have played any part to be involved. I would have played a cat, if there was a cat to play.

Were you a fan of the book beforehand?

My mum got me the book for Christmas and I completely devoured it in one reading. I was due back to [film] Dublin Murders the next day and I was like ‘I’ve got lines to learn but I can’t stop reading, can’t stop’. I was so sad to finish it.

Normal People by Sally Rooney is being adapted into a TV series for the BBC

In many ways, the relationship between Marianne and Connell is reflective of the first love experience endured by young people universally. What is it about this particular story that has really spoken to millennials?

It’s so simple but I feel like every generation, every gender can put themselves in the shoes of these two young people (Marianne and Connell). I know people in their 50s and 60s who are as equally blown away and can relate to it, its incredible for such a young writer (Sally Rooney) to be able to achieve that.

I was definitely thinking back to my previous relationships and how I got things wrong and you know, you misinterpret something for something else and let your head get in the way. It’s relatable on so many levels. 

I also think it’s so important for kids these days to see what love and intimacy can look like, especially with the whole conversation going on around consentNormal People is an incredibly intimate show, there are a lot of love scenes in it and it’s beautifully done. Porn saturates so much of the conversation around sex for kids; let’s show them how love can be. 

It’s also about not being afraid. You only have one life so love, fall in love, get hurt, live your life to the fullest and don’t be scared to throw yourself into being in love.

Look at Marianne and Connell. They spend years avoiding being in a relationship or labelling it when they could have just got together when they were younger and been really happy.

It’s tragic at times because as the reader, we can see that they are misinterpreting each other. Maybe you have to go through that process when you’re young in order to have a real, meaningful relationship.

How many relationships have we been in where its like, are we together, are we boyfriend and girlfriend? What does that even mean? We’re too scared to ask the question, we’re afraid of the answers. It’s a learning curve.

Daisy Edgar Jones
BBC Normal People: Daisy Edgar Jones will play Marianne in the TV adaptation of Sally Rooney's novel.

Sally Rooney is executive producer of the series, what was it like to work with her?

I only got to meet her at the reading and I was a bit nervous. Like with Tana French, they have given birth to these characters, so to see them in real life … I might have been different from what they imagined.

I just hope she thinks I’m okay for the part. I think she’s such a genius!

Images: BBC 


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Lucy Robson

Lucy Robson is an digital writer for, who enjoys chasing trends and writing about books, film, TV and other lifestyle and feminist news.

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