“Wicked Little Letters” finds Olivia Colman and Jessie Buckley as enemies in a 1920s poison pen letter scandal that only seems to be a clever screenwriter’s fantasy.

Because, strangely enough, it all happens to be true.

Neighbors Edith Swan (Colman), a Bible-quoting spinster living with her aged parents, and Rose Gooding (Buckley), a widowed Irish immigrant with a young daughter, couldn’t be more different.

Edith virtually defines the era’s proper, corseted Englishwoman while the uninhibited Rose in her loose smocks rarely gets through a sentence without unleashing  F-bombs.

When Edith is horrified, traumatized even, by receiving obscenity-strewn hateful letters, she and the police immediately point to the most obvious suspect, Rose, who’s soon locked up.

“The fact that Jesse’s Rose isn’t corseted says so much about her freedom,” Colman, 50, said in a Zoom interview from Manhattan.  “She’s decided, ‘Screw this. I’m not going to be held back.’ So she is living the life that she’s chosen. But these other women are so restricted, aren’t they?”

Edith is more than a bit of sanctimonious pickle but for Colman, her comical contradictions were irresistible.

“Very simply, I really thought it’d be fun to play her. She looks lovely and is all sort of pious and fluttery eyelids and butter wouldn’t melt — and then you find out there’s a whole lot more going on! Which of course there is with all human beings. But I just thought it’d be so much fun to play both those things.”

Among the world’s most honored artists, Colman isn’t one to rest on past triumphs.  She’s recently starred in “Wonka,” a “Great Expectations” miniseries, made a guest appearance on “The Bear” and is now filming “Paddington in Peru.”

“I have this plan in my head that I’m going to do one film a year — and that’s never happened,” she said cheerfully. “Everyone wants to work because of ‘I might never work again.’ Every actor has that.

“When this appeared, I wanted to do it because I thought it would be fun.  I love the female-centric nature of it. It’s in the UK which is great, I’m not far from my family. And I love working — I think that’s our job.”

Among her many Emmys, Globes and BAFTAs is the Best Actress Oscar for “The Favourite.” Does he have a special place in her home? Does she ever say, “I’m going to bring you a little buddy one day”?

“I don’t talk to him enough. He’s in a cupboard. Because I feel a little embarrassed when people come to the house. It feels a bit showy-offy. He is very special and I do go and say ‘Hello Shiney.’ Maybe I should say, ‘I’m going to bring you a friend.’ I’ve never tried that.”

“Wicked Little Letters” opens April 5