Only Murders in the Building season 2 killer reveals costars didn't know secret twist while filming

Warning: This article contains spoilers about the Only Murders in the Building season 2 finale.

You can't say Poppy White (Adina Verson) isn't committed to her job on Only Murders in the Building. But in season 2, the aspiring podcast host/assistant to Cinda Canning (Tina Fey) went a step too far by committing the very murder that their podcast was investigating.

That's right — not only did Poppy recently reveal her true identity as murder victim Becky Butler (from the All Is Not OK in Oklahoma podcast referenced in season 1) a few episodes back, but in the brilliantly twisty season 2 finale (now streaming on Hulu), she was also exposed as the killer. It turns out that Poppy killed Bunny (Jayne Houdyshell) and framed Mabel (Selena Gomez) so that she could solve the murder on her podcast, finally getting the fame and glory she's always wanted. But Mabel, Charles (Steve Martin), and Oliver (Martin Short) teamed up with Cinda to outsmart Poppy and catch her red-handed on a live episode of their podcast instead.

"I found out that Poppy was the killer right before we started shooting season 2," Verson tells EW. "When they asked me to come back for season 2, there was some weirdness about the kind of contract that they wanted and the kind of billing [I'd have] and instead of just being obtuse about it, they set up a zoom with [executive producers] John Hoffman and Jess Rosenthal and they told me what Poppy was getting up to this season. I was so excited/shocked/terrified."

Verson adds that while she didn't have all the details from the beginning — "Those came as I got each script, which was a week before we would shoot an episode" — she discovered early on that she was one of very few people on set who knew the big secret all season long. "It was a big surprise when I first got to set and I realized that nobody else knew. I just assumed that other people would know, but nobody knew."

Below, Verson tells EW what it was like keeping that twist a secret from everyone (including the rest of the cast — and even her own parents!), filming the killer reveal party, what this means for Poppy/Becky's future next season, and more.

ENTERTAINMENT WEEKLY: Did you accidentally spoil Poppy's big reveal for any of your fellow cast members who didn't know the secret?

ADINA VERSON: No, I did not. It wasn't until we shot the passageway scene in episode four — where I sneeze and see Lucy — that was actually me filming that scene, and I came down to set wearing the suit and holding the ski mask. The crew members were all like, "Oh my gosh, wait a minute. Is it Poppy?" So then they were all in on the secret. That was fun, as I went along with different episodes to have the crew know, but they still kept their mouths shut. Selena and Martin didn't know until they got the script for episode 10.

When you were filming those scenes, were you ever filming with Selena and Martin and Steve and they just had no idea, or did they film their coverage at a different time?

That scene was filmed separately. Nobody was on set that day except for me and Lucy, but I don't think that she quite put the pieces together. That was one of her first days shooting, also, so I don't know that she registered that meant that I was the killer. After that scene, they kind of realized that they couldn't have me do all of the masked scenes because they had some trouble camouflaging my body. They ended up putting me in these big pants underneath the suit so that you couldn't see my legs when the lights shined through the suit, and then they were having me hunch so that you couldn't see my boobs and stuff like that. They eventually were like, let's get a bunch of different body doubles for every time, and when they were shooting on location, so that no paparazzi or people who saw us on the street or would be like, "She's in the scene at the diner with Bunny!" I actually don't think that Jayne Houdyshell, who plays Bunny, even knew.

Wow, this is so much more cloak-and-dagger than I thought. Even behind the scenes!

Yeah, it was really fun to have that secret alongside Poppy.

What was it like having to live this double life both onscreen and in real life while filming, all the way up until the finale aired?

I'm a really impatient person, and I'm bad at keeping secrets, so it was a good test and a good lesson for me. I mean, we're talking right now before episodes nine or 10 have come out and my parents still don't know! [Laughs] I'm excited for them to see it. It's been weird, and kind of humbling, being like, "Will people be mad?" I'm kind of sad for people to possibly hate her, even though she did something that you should hate somebody for.

True, this twist and reveal really does shift your entire perspective of who you thought Poppy was this whole time.

Yeah. She's really smart, but her Achilles heel is that she needs recognition. She's been living this life of secrecy, and that can fog your perspective of morality and consequence almost in the same way that lot of addiction is grown in secrecy so that it's easy to compartmentalize.

How did you go about portraying Poppy this season, knowing from the beginning that she's actually Becky in hiding and she's keeping so many secrets?

I went back and forth about this quite a bit, but I decided that Poppy's a really good liar. When Poppy is Poppy, I didn't want to hint that she was playing something, or thinking something underneath what she was playing. But then getting to transform into Becky was just a really sweet experience, once they put on the wig and I didn't have the glasses on, to just feel so stripped down and vulnerable. She's like this little soft, wounded creature and I have a lot of empathy for her. I feel like that little wounded creature is where monster could come from, but under every monster is a little wounded creature.

What was it like playing the moments when Poppy finally gets to reveal that she's actually Becky and the killer?

Yeah, in episode six when Poppy decides to tell Mabel some secrets, she's kind of snapped a little bit. Her plan has shifted and she's decided to frame Cinda because she can — at this point, she has all the tools and information that she needs to frame Cinda. She just wants to bring Cinda down, and it's really smart of her to give a little information, some secrets, knowing that they'll definitely come back to her at some point. And then when they do come back, when Mabel meets her in the recording studio, she's playing her by revealing a truth, that she's Becky Butler, that's a huge way to be able to bring Cinda down, because she knows that there was fake evidence planted and she could blame that on Cinda. That was fun to be able to fully be waist deep in how good of a liar and schemer Poppy is, without giving anything away.

And then in the killer reveal party, that's just ultimately when Poppy snaps, which I think is really sad because she just has never gotten recognition, as Becky Butler or as Poppy. She is a really smart, talented human, and her boss and idol knows that she can be manipulated by squashing her in any opportunity she has. Even though she's done this unforgivable thing, stabbed Bunny eight times, this whole party, the way that they set it up has been to manipulate her feelings. That just reveals that Cinda knows how to push Poppy's buttons and has been doing it on purpose the whole season. It's just sad to me that there's so much unkindness towards Poppy. But as somebody who suffers from anxiety, I also was able to get into that pretty easily, where I feel like her world is crumbling, she's so confused, she's just been totally gaslit by this huge room of people, and it's so disorienting. As somebody who is power hungry and likes to be in control, because she has orchestrated this whole world that she lives in, to have it suddenly turn on her, it must be really terrifying. I feel like she just goes into having a panic attack and then her shell crumbles and she's just this little wounded bird again.

That was the hardest scene, the killer reveal, honestly, just because I wasn't completely sure how to play it. I ended up just doing a bunch of different things and then they edited it really beautifully. My first instinct was to laugh, because Poppy wants recognition and this in a weird way is her being recognized for all that she has done. There were some takes where I was laughing, and some takes where I felt like she was having a psychotic break, but I'm sure that would've felt too much like season 1 and it would not have been a good idea to have the murders in season 1 and season 2 be a crazy woman. That would've been a bad choice. But then also feeling the shame of it and the weight of it and the tears ... there were so many different ways I could see it going, and we were able to film all of them. I didn't know which ones they were going to choose, so when I finally got to see episode 10, I was almost surprised at how sad it is and how much you continue to feel for Poppy, and what it means to empathize with the murderer.

And people were really surprised that Poppy was the killer! I think that maybe some of the actors didn't get the full script ... I don't know why, but people were still confused while we were shooting it. They were like, "Oh, it's Alice." I was like, "Wait, no, have you read the next few pages?" Poppy got to come be revealed in front of the whole cast just doing the scene.

Looking ahead to season 3, have you spoken with the producers about what Poppy's arrest means for your future on the show? Could we see Poppy again, like how Amy Ryan's season 1 killer Jan returned this season?

I hope so. Nothing has been confirmed. If I don't go back I'm really going to miss it, but I am going to be excited to be able to be a viewer not knowing what's going to happen. I know that they're writing season 3 right now, and I definitely dropped some hints and some ideas that I had for how Becky might be able to fit into that because I would love to see how prison treats her.

Maybe Poppy/Becky still works with Cinda on the next season of their podcast — but while she is behind bars.

That would be amazing. Maybe there's some prison scandal and Poppy has the inside scoop on it.

This interview has been edited and condensed for length and clarity.

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