Frank Warren says he thought of it as “an interesting prank”: in 2004, he handed out 3,000 self-addressed postcards to strangers, asking them to mail their secrets to him. Little did he know the lovingly crafted, soul-baring results would grow into a global phenomenon, leading to the most visited ad-free blog in the world, called PostSecret.com, plus several best-selling books, speaking engagements around the world, gallery exhibitions, and, now, a new stage show.

“When the secrets told their own stories, when they led to me selling my business and spending 50 hours a week on it, it turned my life upside down. But it’s given me so much meaning,” says Warren, who has received more than a million postcards since, curating and posting the artful creations every Sunday on the site, which has seen 700 million visits.

Speaking to the Straight from his home in Germantown, Maryland, he says that looking back on the endeavour, he’s struck by the sheer quantity of anonymous secrets. Some are funny (“I shroomed at Disneyland and Goofy knew,” surrounded by psychedelic artwork), some are painful (“I don’t smile anymore,” placed over the mouth of a smiling woman), and some are both (a photo of a guy in a graduation cap flipping the bird, with the words “This is for all the teachers and tutors that said ‘Graduation isn’t for you’ ”). “Secret after secret, day after month after year: there are so many secrets waiting to be shared. And there’s millions more deeper secrets out there.”

Warren’s biggest discovery has been how much secrets can tower over us and burden us. “Sharing a secret can be contagious and also inspire other people to realize that the biggest burden can be keeping the secret.” And those burdens can sometimes have serious consequences: Warren’s project has led to him raising more than $1 million through the site for suicide prevention.

If anyone knows the release that can come from sharing our most hidden thoughts and experiences, it’s Vancouver writer-performer TJ Dawe, acclaimed here for his Fringe festival hits like Medicine, his confessional about the revelations he had about himself after taking the shamanic brew ayahuasca. So it seems he’s the perfect match for a project that brings PostSecret’s stories to the stage. He directs PostSecret: The Show, created with actor Kahlil Ashanti, producer Justin Sudds, and Warren, with its multimedia array of projected postcards and music, at the Firehall Arts Centre.

“People keep secrets because they believe they could never tell someone because they’re alone,” Dawe tells the Straight over the phone, explaining that part of him was convinced he would lose every acquaintance he knew for the things he divulged in Medicine. “It turned out these protective voices were entirely wrong. It opened up a lot of conversations and a lot of people wanted to tell me their secrets. It’s been hugely valuable to me therapeutically.”

But turning the postcards, and the site’s email responses to them, into a theatrical show has been a challenging, five-year process. Not that Dawe didn’t see the potential right off the bat: approached by producer Sudds to turn the viral blog into a show, he picked up Warren’s first book and said he was in tears within the beginning pages. Still, Dawe says the closest theatrical model the creators had to work with was The Vagina Monologues, a show built from interviews. But here, the performance would pull together stories that played out online, both visually and in words—“a theatrical sculpture of found materials”, as he puts it.

In the production, actors Ashanti, Nicolle Nattrass, and Ming Hudson bring to life some of the crowd-sourced stories and email responses, with the postcards appearing in projections as they speak. But there’s another integral element to PostSecret: The Show: the chance for audience members to share their own secrets beforehand.

“Some are read at the top of Act 2, and they’re all set out to read after the show, and after the show people can write secrets or messages to those that have secrets,” explains Dawe, who was struck, in the production’s initial run in Charlotte, North Carolina, by how the experience compared to reading the submissions online. “It’s incredibly powerful to get 150 people in the same room reading the same postcard at the same time.”

What’s interesting, Dawe points out, is that in this era of social media, people are used to sharing things about themselves online—but only the good things, like a “highlights reel”. “So there’s this dichotomy: I’m revealing myself all the time, but there are things I can never say.”

With Warren mediating the interactions online, PostSecret has been able to create a different, more authentic connection between people, using the low-tech, handmade postcards in the digital sphere. But at the show, audiences will hear about PostSecret’s failed first attempt at launching an app that allowed anonymous responses. “It was the top-selling app in the U.S. and Canada, but we had to kill it three months later because of the bullying and breaking of rules and values,” Warren says. A newly designed, archivelike app, PostSecret Universe, has just launched.

Through multiple formats, and now through the stage, PostSecret is determined to show people that no matter what they are hiding, they are not alone. In the past 10 years and the hundreds of thousands of postcards that have arrived at his mailbox in Germantown, Warren says he has seen recurring fears and desires emerge. “Probably the biggest theme is the search for intimacy. It’s the struggle so many of us are in the middle of: to find that one person or two of the tribe that gets us,” he says.

In fact, the PostSecret show may really be about finding true connection in our supposedly hyperconnected universe. And that’s a big reason why Dawe hopes the new production will have a long touring life. “I think society needs to know that there’s a safe place to tell your secrets,” he says.

PostSecret: The Show runs at the Firehall Arts Centre from next Wednesday (January 21) to February 7.