How Only Murders in the Building disguised its killer twist

The development will come as quite a shock to viewers who have been presented with a number of red herrings over the latest batch of episodes, including Tina Fey's Canning, Cara Delevingne's Alice and Michael Rapaport's Detective Kreps.

Adina Verson, who plays Poppy/Becky in Only Murders in the Building, explains that a different performer donned the killer's disguise in certain scenes to prevent viewers from identifying her.

"It was me in the passageways with the sneezing," she began, referring to a scene which helped the Only Murders trio build their case. "I think they were hoping that I would do the other [killer encounters], but they could see my body shape a little too well."

The creative team experimented with dressing Verson in clothes that would purposefully obscure her usual appearance, but alas, couldn't settle on a satisfactory solution and deemed the risk of a misjudgement too high.

Verson continued: "They were like, ‘Can you hunch a little bit so we can't see your boobs?’ And then they had me go back to costumes and get these big Carhartt [workwear] pants to put on under the suit so that you couldn't really see the shape of my legs.

"And then they did some movement coaching with me… and I think eventually they were like, 'Let's just get somebody else so we don't give it away.'"

For some time, only the writers and senior executives knew that Becky was the perpetrator, with the news slowly trickling down to the crew (on the day of filming the sneezing scene) and later the Only Murders in the Building cast.

"When I came down to set in that costume, nobody else was on set that day except the actress playing Lucy, and so it was like a big reveal to the crew that Poppy was the killer. And so, then the whole crew knew, but none of the cast knew," recalled Verson. "So it felt like Adina, the actor, was keeping a secret while Poppy was also keeping a secret. It was very meta."

This secrecy required Verson to think on her feet on more than one occasion, including during a conversation with one of the show's main cast members: pop star and former Disney Channel favourite Selena Gomez.

"I didn't know that nobody else knew until I got to set for the first episode, and I just had like one line… in a little scene with [Gomez's] Mabel," she explained.

"When we finished, Selena was like, 'Will I see you again?' And I was like, 'Oh… yeah? Maybe?' And then I was like, 'She doesn't know'. Like, she thought that maybe that was my only thing this season."

Poppy's unveiling wasn't the only surprise in the Only Murders in the Building season 2 finale – there was also a shock cameo from a major Hollywood star.

Only Murders in the Building is available to stream on Disney Plus – sign up to Disney Plus for £7.99 a month or £79.90 a year now. Check out more of our Comedy coverage or visit our TV Guide to see what's on tonight.

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