Spoiler Talk with Pippa Bennett-Warner, Star of 'Moonflower Murders'

Our reintroduction to the world of Susan Ryeland (Lesley Manville) in Moonflower Murders, the follow-up to Magpie Murders, brings brand new characters into the mix, and perhaps none is more memorable than Madeline Cain, played to perky perfection by Pippa Bennett-Warner. In the story within a story, Miss Cain inhabits the fictional novel by Alan Conway (Conleth Hill) and is the brand-new Gal Friday to Conway’s 1950s-era detective, Atticus Pünd (Tim McMullan). Miss Cain is a fascinating mixture of propriety and boldness, eager to please her new boss yet driven by a secret obsession.

While Miss Cain’s motivations remain hidden until revelations in the final episode, her personality spills out throughout each scene she graces. In a particularly memorable exchange, she challenges Oscar Berlin (Mark Gatiss): Berlin recounts his supposed alibi – walking on the beach – when Miss Cain realizes he’s lying. She tricks him into telling the truth by bluffing and spinning her own lies, claiming the beach in question would have been at high tide and impassable. When she comes clean, Pünd is impressed and the audience has an indication of her deceptive capabilities.

Telly Visions sat down with Pippa Bennett-Warner to talk spoilers, character details, and her favorite Anthony Horowitz novels.

This interview has been edited and condensed for clarity. Spoilers ahead!

Telly Visions: So, now that we've seen the finale, we need to know: Did you guess the murderer, either in the present-day story or the novel story, as you read the script?

Pippa Bennett-Warner: No, I didn't! It was such a pleasant surprise. I was like, Oh my God, Madeline! Oh my God, Aiden! And Will [Tudor] is just gorgeous as well. But no, I didn't guess anything. That's the genius of the writing as well. It keeps you going and then surprises you at the end. It's excellent crime writing. His brain is amazing.

TV: We talked to Horowitz about how he plots, and it's fascinating. We know that in the Atticus Pünd novel, there are actually three murderers. Did you think it was always Miss Cain’s intention to kill Melissa James’ murderer, John Spencer (Rupert Evans)?

PBW: The obsession and the love runs so deep for Melissa James; Madeline was almost trying to do the work of God. I feel like she believed she was doing the absolute right thing at that moment. We had this ongoing joke that Madeline actually killed her old boss at Associated Biscuit, that she's evil but covers it all with this nice demeanor. You can read it in many ways. But I think she's avenging the death of someone who I believe she's in love with.

TV: Can you discuss Miss Cain’s obsession with Melissa James? Have you experienced that level of scary super fandom? You've done some voiceover work for video games.

PBW: So firstly, Madeline and Melissa: She’s entirely besotted by her. I’m imagining her little flat had all the (movie) posters. Catherine Argue was our very brilliant hair designer…the wig I’m wearing in the show is dyed red to match Melissa James’ hair. Madeline’s that committed to this “relationship.” Do you know how you can watch somebody and think you know them? That vibe? She’s totally besotted, super number one fan, and she does what she does because she feels it’s the right thing to do. I’ve never had any super fans; I’ve had some odd things, but I don’t have any Madeline Cains.

I'm not a gamer, but my most recent project, Elden Ring, and my game and character, Malenia, have garnered much attention. I enjoy it; I get messages asking if I'll do little recordings. But now it's quite difficult to do another (game) because Malenia was so fun. Malenia is so iconic now—apparently, she's incredibly difficult. She takes 150 hours to beat! That's a lot of time. Respect to the gaming community.

TV: Madeline Cain is quite bold and quick to challenge people. What makes her so assertive?

PBW: She has this endearing keenness and wants to impress her boss. This is a new relationship; she’s fresh from Associated Biscuit and wants to impress Mr. Pünd. He is also quite generous in allowing her to speak so front-footed, which is quite fabulous as well. She wants to be heard, do the right thing, and stand up for what’s proper, even though she’s harboring this secret for most of the show.

TV: What do you like best about her?

PBW: I like how she’s a bit kooky and spirited. I’d love to see what she does behind closed doors. Is that who she actually is; is she presenting that? Is she actually cold-hearted? There are so many layers to her that she’s quite interesting to unpick. I don’t have a character in the modern-day world; there are a few of us that don’t. If she did have one, I wonder who that person would have been. It would have been really interesting to see the two.

TV: Do you have a preference between doing period pieces versus modern day?

PBW: I always like to keep things varied and mix it up. Throughout my career, I've done a mixture of the two. There are things about modern-day, logistical things – you can get yourself into your own costume. When I did Harlots for three years, you had to have somebody to get you in and to get you out. But there is nothing better than using (the wardrobe) – and you can do this in the modern day too, but particularly with a period, the clothes can help to build character. 

That's what I found about Moonflower Murders: [Costume designer] Annie Hardinge's work was so brilliant. It just helped me stand, hold myself, and think differently. I had a bag to look after, gloves, a hat that had to be perfect, and clothing. I could barely eat, that sort of thing. I used it all to make Madeline as rich as I could.

TV: You talked about the clothing getting you into the period and the mindset. How else did you create Madeline Cain and get into that world?

PBW: I always start with the script, and Anthony's such a brilliant writer that most of the work was done for me. I was about 15 pages into the second episode [when Miss Cain first appears]. I knew exactly what I wanted to do with her; she just really leaped off the page for me. I followed my instinct and my gut. 

Also, at work, I was trying things. I hadn't seen the show, but I feared my performance would be quite big because I was just playing, and Rebecca didn't say anything, so I just continued doing it. Playing off Tim McMullan and Danny Mays (as Chubb) made me find her even more because we each had a little space within that throuple, and all the characters bounced off each other. The script, the clothes, and working with Tim and Danny were just heaven, as you can imagine.

TV: How did you get involved with Moonflower Murders, and what about the script appealed to you?

PBW: Very traditionally: I got sent the script, did a self-tape, and didn't hear back for ages. I just assumed it had gone away, as these things do. Then they came back and said we’d like you to do it. It was an immediate yes, one I didn't have to think twice about because I grew up being the biggest fan of Anthony Horowitz’s work; to get to play an original character of his was really exciting. I thought the scripts were fun and clever. (Miss Cain) was delightful in every way. Sometimes you get those jobs, and you're just like, "Yep, I need to go and do that," and this was one of them.

TV: What’s your favorite Horowitz story?

PBW: Groosham Grange; I liked all of those books. Alex Rider. I mean, all of them. I was obsessed with his work. I grew up in the early 90s, and he was one of the authors who stuck out. I think we were given a book of his at school. I just kept finding all of his work and adored it, and he's also just such a nice man. Now I know that he's a lovely man and a brilliant author? It makes such a difference.

TV: Do you have any favorite on-set memories?

PBW: We had the best month! The 50s stuff was all shot in the first part of the shoot. I think it's one of my very favorite jobs ever. Every day was just a complete delight. [Director] Rebecca Gatward is just fantastic at setting a really lovely tone on set. Everybody felt super comfortable, and we were able to play. I think the whole of those first four weeks was just heaven. I can't pick out a moment because it was all divine, and we all got on really well.

TV: I'm sorry we won't be seeing you if there's a third season because your character has run her course.

PBW: I'm devastated. I have spoken to Anthony. It's like, please, I'll just be a tree in the background; I don't care! And he said no, so it is what it is. 

It was very special, I have to say. You don't always get that on TV jobs, film jobs, you just don't. But we lucked out. We had a cast and crew screening a few weeks ago, and everybody's work is just gorge. You can see the chemistry on screen.

All episodes of Magpie and Moonflower Murders are streaming on the PBS app, PBS Passport, and the PBS Masterpiece Prime Video Channel. The book that will make up a potential Season 3, Marble Hall Murders, arrives on selves in 2025; hopefully, it'll bring along a renewal for a final set of episodes as well.