Note: The following story contains spoilers from Season 4, Episode 7 of “Only Murders in the Building.”

After realizing in last week’s episode of “Only Murders in the Building” that the season 4 killer has been watching the trio, Charles, Oliver and Mabel leave the Arconia and New York City to hide in Charles’ house sister Doreen on Long Island. who is played by Melissa McCarthy.

Showrunner John Hoffman told TheWrap that working with the “Bridesmaids” actress on the Hulu comedy had been a dream of his for years and was previously upended by the pandemic. (He declined to reveal details about what her role would have been at the time.)

“I just love her so much. I think she is extremely talented, both in funny and dramatic ways. I tried to get her on the show a few years ago, and it was deep in the middle of COVID. There were a lot of complications and we looked at each other and said, ‘We can’t do this right now, can we?’” Hoffman said.

“As far as planning goes, with this incredible group of people, it’s always a dance of, ‘Wait a minute, OK. Wait no, not available. Who’s available now?’ But this is the window we have. This is Meryl Streep in an episode, which we committed to when we shot this anyway, plus this incredible collection of actors that we wanted for this episode. And then, lo and behold, Melissa’s schedule opened up when we were really at the last minute,” he added.

Hoffman quickly called McCarthy to explain what role she would be playing, which she immediately agreed to.

“From that moment on, when I described the character and the story, she literally said, ‘I’m dropping the phone. I can’t believe what I’m hearing. This is the best thing I’ve ever heard.’ I’m like, ‘Oh my god. Real? I’m so excited. ”

It wasn’t long after that that McCarthy fully immersed himself in the character.

“I’m telling you, she just arrived in full bloom, just a complete genius. She had a bag of wigs she wanted to try on and landed the one she wanted. She had French tips about feet and hands. She had the look and vibe of Long Island,” Hoffman said. “And then Dana Covarrubias completely costumed her in one day, and she was Doreen from the start, bringing crazy, insane brilliance to comedy and then killing you.”

One of Doreen’s quirks is an obsession with collecting dolls, which she developed as a coping mechanism after her adult children left home.

“I didn’t know that Melissa has her own doll obsession/collection that she shared with me. I saw her early one morning at the Rose Bowl flea market, and I didn’t know her personally at the time. She was looking at a collection of old Barbie dolls and she ended up buying them,” Hoffman said. “So it may have been subconscious, but it was an idea before we were sure she could do it with us.”

McCarthy’s role as Doreen ultimately culminates in an all-out brawl with Meryl Streep’s Loretta over Martin Short’s Oliver, which both actresses were immediately on board with.

“The first time I told Meryl you would put up a real fight for Oliver, she raised her hands above her head and replied, ‘I got my money’s worth,’ which I thought was great,” Hoffman said.

After reviewing the scene mapped out by the show’s stunt coordinators, Streep and McCarthy decided to abandon the original plan.

“Melissa and Meryl looked at each other like they were in the WWE and said, ‘Yeah, I don’t think that goes far enough. We have some ideas about what we would like to do.” And both started rolling up their sleeves and mapping it out themselves,” says Hoffman.

“I was terrified and I saw Meryl turn herself over the couch and say, ‘Wait a minute, we’re going to film this, which means we’re doing it a lot.’ I can’t. What are we doing?” And they just said, ‘Go away.’ They took over and it was a party, they did it all themselves,” he continued. “There may be one shot of a double at one point, but other than that it’s all of them and I still can’t believe we have this madness. But it was great and they were both looking forward to it so much.”

After McCarthy and Meryl finish chewing sets, Zach Galifiankis, Eva Longoria, and Eugene Levy confirm what the audience suspected in the previous episode: that the killer has been keeping an eye on the trio since season 1.

They match the “I’m watching you” lyrics to the same handwriting and note posted on Jan’s door in season 1 and also suggest that the unidentified perpetrator who poisoned Oliver’s dog Winnie is likely the same suspect. And Charles realized that Sazz had planned everything and tried to warn him before she was killed.

Howard also learned and immediately informed the group that Dudenoff’s checks were being cashed by none other than the Westies, providing yet another twist.

“When we created our doppelgänger trio, I really wanted to emphasize that they had perspective and that our trio undervalued them. And then let them do research in the way Meryl says – actors are researchers – and respect that and work with it. And the idea of ​​that felt really good to me at the end of this episode, that after all the madness, they hit one of the biggest twists of the season and woke up our trio,” Hoffman said. “And then there are still big steps to come from that West Tower that will change the narrative and change everything you thought you knew.”

New episodes of “Only Murders in the Building” debut Tuesday on Hulu.