Now, that's embarrassing

In hindsight, it was bad enough that young Jane Roper was so giddy about her first concert -- Billy Joel at the Hartford Civic Center, circa 1990. Worse, she documented the event in agonizing detail in her girlhood diary, which she still owns.

''It was typical teenage hysteria," says Roper, a 31-year-old advertising copywriter living in Medford. ''It starts with me saying how depressed I am that the concert is over. It's pretty embarrassing."

Rather than quietly suffer the rest of her days with the shame -- the shame! -- Roper has decided to exorcise the memory by sharing it. She'll read from her diary tomorrow at the Tribe Theater in the Boston debut of the self-flagellation sensation known as ''Mortified."

With monthly shows already well established in Los Angeles, New York, and San Francisco, ''Mortified" now brings courageous Bostonians a chance to come to terms with their own pathetic teen crushes, obsessions, and humiliations. In addition to Roper, a dozen or so participants -- some of them working writers or comedians, others ordinary day-jobbers -- will read from the deepest, darkest pages of their sophomoric poems, diaries, and mash notes. A rotating cast of participants will contribute each month.

''It's basically this giant group therapy session," says founder and executive producer David Nadelberg -- without the exorbitant hourly fees.

''The whole show has this therapeutic feel to it," agrees Giulia Rozzi, a Belmont native coproducing the Boston show with Nadelberg, as she does in New York. The performers, she says, are getting humbling episodes off their chests; audience members, meanwhile, can laugh cathartically over their own awkward years.

Nadelberg, a Michigan native who moved to Los Angeles to get into television production, says it's become tradition to make himself a sacrificial lamb at opening night in a new city. ''If I'm expecting other people to read their worst stuff, I've got to step up to the plate, too." His own contribution involves ''a love letter that sort of begat the whole 'Mortified' frenzy."

Now in its fourth year in LA, ''Mortified" is becoming a cottage industry of communal emotional trauma -- ''retro rubbernecking," as Nadelberg likes to call it. This fall, a division of Simon & Schuster will publish the first ''Mortified" anthology, and Nadelberg is sorting through various broadcast concepts, from podcasting and satellite radio to television.

Ultimately, he says, the show works best onstage. ''Our goal is to turn this into the next 'Vagina Monologues' or 'Puppetry of the Penis' -- any kind of fringe theater show. To me, that's the driving force of the theater world."

The audience, he says, tends toward the post-collegiate. ''[They're] the people who are on Myspace, people in their late 20s and early 30s. They read Found magazine, they're on Craigslist far too much -- that kind of demographic."

Still, older audience members (and performers) are encouraged to participate, he says.

''My goal has always been to have somebody above the age of 50 or 60 onstage. The whole point of the show is that we're all that same kid, whether we're popular or not, rich or poor, ugly or hot, gay or straight, black or white. We're all that dorky kid at the core."

When Rose Azrael, a 21-year-old Emerson College student, takes the stage, she will become one of the youngest performers ''Mortified" has had to date. She plans to read from a high school journal entry about her experience in a Jewish youth group.

On the phone from her home in Pennsylvania, where she was on a school break, she explained her sneaking suspicion that such youth groups are something like early dating services that parents send us to.

''Dad, I'm on the phone!" she suddenly hollers.

Such a young performer might make Nadelberg a little uncomfortable. A self-proclaimed ''angstologist," the producer says he always frets about the reaction of the youngest audience members. Will they have enough distance from their own embarrassing teen dramas to see the humor?

But Azrael isn't worried -- she's mature for her age. ''I'm an only child, so I hung out with adults my entire life," she says. Besides, high school already seems ''ancient.

The exquisite pain of puppy love makes up the majority of material at ''Mortified" auditions, say the producers. And it's not just the girls. ''At some point," says Nadelberg, ''every guy thought for about a week that he could be the next Jim Morrison."

But Rozzi and Nadelberg work hard to identify less obvious sources of comic relief. Past performers have read from their letters home from summer camp, their precocious pronouncements on the world of fashion, and journals detailing the daily developments on favorite soap operas.

''They read from school assignments, college applications, bad poems about the environment, and celebrity crushes," says Rozzi. ''It's a good mix."

North Andover native Liz Simons, an aspiring stand-up comic and scheduled ''Mortified" performer who also runs adult kickball leagues in Boston, says she knew she was perfectly suited to the ''Mortified" sensibility as soon as she heard about it: ''[The concept] spoke to me, which is so unbelievably corny."

To this day, says the 26-year-old, ''when something embarrassing happens, my way of dealing with it is to call out to it. If I fall, or do something stupid with a boy, I tell everyone. They're going to find out eventually anyway.

''Maybe that's why I'm still single."

That's the kind of self-deprecating humor Nadelberg wants for the show. ''It may not get easier when we're adults. Life is still complicated, ugly, and gray, and people are still mean to us.

''The message is," he says, ''you survive."

"Mortified Boston" debuts tomorrow at 8 p.m. at the Tribe Theater, 67 Stuart St., Boston. Tickets are $20; 617-510-4447. For more information, go to www.getmortified.com.