It started seven years ago, with a favor: One of Robyn Lynne Norris’ friends had signed up with OkCupid and asked her to review her online dating profile.

Back then, Norris, a 20-something “hopeless romantic,” knew nothing about online dating. Newly arrived in Los Angeles and lonely, the writer-comedian had just come off a bad breakup — to a fellow comedian who, during their monthslong gig on a cruise ship, hooked up with the woman in the cabin next door. On Norris’ birthday, no less.

And so, with time on her hands and angst in her heart, she agreed to help her friend — only to find she had to submit a bio of her own before she could view someone else’s. Within five minutes, Norris scratched out a jokey profile of someone she considered utterly “undateable”: a 28-year-old LA woman posting as “Tracylovescats.”

As the dating site required, she gave Tracy a self-summary (“I love KITTIES!”), a goal (“Trying to act and playing with my kitties ALL day long!!!”) and a typical Friday night activity (“Eating chocolate and playing with my KITTIES!!!”). She attached a goofy-looking photo of herself, posted it and went on with her life.

Three nights later, when Norris met her friend for dinner, she logged on — and found that her kitty-loving alter ego had pawed a nerve. Along with some punny and profane come-ons were a lot of playful responses, along the lines of “meow, meow” and “purr, nap, yawn.” And they were from men. More than a hundred of them!

“It was crazy,” Norris tells The Post. “I thought, ‘I’m so painfully single — and this crazy cat lady is more popular online than I am in real life!’ ”

So began her yearlong experiment into who, if anyone, might be considered “undateable” in the wide-open world of the internet. Those profiles and responses gradually blossomed into a show: “#DateMe: An OKCupid Experiment,” now playing off-Broadway, has a cast of eight, several musical numbers and a downloadable Tinder-like dating app, #DateMe, that lets theatergoers connect with each other during the show.

‘I think it was pretty impossible to think these [profiles] were real people.’

At the heart of the show is Norris (played by actress Kaitlyn Black) and her own lightly fictionalized life story, plus verbatim snippets from the 38 preposterous OkCupid profiles she and several friends created.

Enter Clean4U84, who billed herself as “a smart girl with a good head on her shoulders. A head that likes to be shampoo’d . . . scrubba, scrubba, scrubba” and whose favorite “book” was the Bed Bath & Beyond catalog.

“She got hundreds and hundreds of responses,” Norris says. “I think because it was so funny.”

Also popular was BoobsandWangz, a 32-year-old law firm receptionist whose lifelong dream was to work at Hooters. That generated a lot of interest, too, Norris says: “Lots of people played along, telling her they knew a manager” at one of the franchises.

But before Norris and Co. posted any of their fake personas, they set some ground rules.

“We didn’t want to catfish anyone,” she says. People who seemed genuinely interested in kitty-loving Tracy or CokedOut — a 32-year-old Boston brunette with a yen for Coca-Cola — were told the women were off the market.

“I think it was pretty impossible to think these [profiles] were real people,” Norris says. “But if they didn’t know, I’d write back and say, ‘Hey, you seem wonderful, but I just started seeing someone.’ I wasn’t into ghosting.”

She and her collaborators also vowed not to use stock art: All 38 profile pictures were photos of either the Los Angeles-based Norris or her friends.

Along the way, she learned a lot about online dating, and what it takes to elicit the most interest.

“I realized the more specific you are in your profile, the more responses and messages you’ll get,” Norris says. “Everyone says they love to laugh and travel, but the more specific you make it — the more you put in what’s weird and unique about yourself — the more interesting you’ll be.”

She also believes the stereotypical online dater is just that: a stereotype. “People think everyone on the internet is disgusting or just wants to have sex,” she says. “But I found myself connecting with funny people, lovely people.”

Barely had her experiment ended, in 2013, when Norris herself felt ready to connect. But before she went online in earnest, she met someone in real life, at a comedy club. Atul Singh, an improv and sketch comedian, won her heart before their first dinner date, just by giving her a curated list of restaurants to choose from.

“He did a lot of research,” she says. “I thought, ‘This is already the most thoughtful person I’ve gone on a date with!’ ” They wed in 2017 with two ceremonies. In the Hindu one, Singh rode in on a horse — her knight in shining armor.

“I think the experiment helped me get ready for him,” Norris says. “I was so closed down before . . . The internet gives you the feeling that you can reach out. People want to connect.”