In 1993's iconic Hocus Pocus, Najimy's Mary Sanderson has a crooked smile, a detail Najimy, 65, improvised during shooting. In the newly-released sequel, Najimy continues to use the misshapen smile, but this time on the other side of her face.
"It's on the other side mainly because it's so hard for me to do it on the side I did it on 30 years ago," Najimy told Entertainment Weekly in an interview published Friday.
The actress, who said she knows fans will probably "go into deep detail about why," noted that the side change is explained in the sequel for fans seeking answers.
"We can justify it because there's a scene at the beginning where Winnie slaps me, and my mouth goes to the other side," she said, speaking of Bette Midler's character. "And then she slaps me again, and it goes to the other side and sticks."
Charles Sykes/Invision/AP/Shutterstock Kathy Najimy at the Hocus Pocus 2 premiere
Najimy and Midler, 76, star alongside Sarah Jessica Parker as the Sanderson sisters in both Hocus Pocus installments.
During her conversation with EW, Najimy also explained what made her come up with the crooked smile in the first place. "It's just something I came up with the first week," she said of shooting the first movie. "This is a big comedy, so you don't have to be subtle or have a 40-page Shakespearean backstory."
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Najimy recently revealed to PEOPLE that she broke a rib when she paused filming the sequel while on a holiday break late last year.
"The day I wrapped, I went over to my friend's house. And I saw that she had one of those machines that you put your legs in and you go upside down and it stretches you, because I have one. And I said, 'Oh my God, I have one of these in home,' " she said.
But, once Najimy got into the machine, "It flipped up, my foot didn't quite make it into the thing ... and I fell like an accordion," she recalled. "And broke my rib."
"So my whole week off that we were supposed to enjoy the holidays, I was healing, but it's fine," Najimy added. "And then I was back at work wrapped up. Half the movie, I have a broken rib."
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Najimy also said her character Mary — the frequently confused, children's-souls-obsessed middle Sanderson sister — came back "freakily easily" for her, despite almost three decades having passed since she last played Mary on the big screen.
Of the first film, she reflected, "It just really is very generational, but nobody is more surprised than we are about how this movie and these characters have just flooded through people's Halloweens and they really take it seriously. They really, really look forward to it. And it's flattering."
As for a third installment of Hocus Pocus, she's adamant about the "never say never" mantra.
"It was fun, but it's not nothing. It's a lot, but who knows? ... Who knew that almost 30 years later we'd be doing this sequel?" she told PEOPLE, joking, "I think if we did it 30 years later again, well, there would be walkers and canes involved. The flying might just be a little one-foot blip off the ground."
Hocus Pocus 2 is currently streaming on Disney+.