POTOSI, Mo. — Jen Leffler first escaped into the world of Harry Potter as an adolescent in suburban Chicago. A decade later, the love affair continues. Only now, it means taking road trips to concerts across the country.

Inspired by the characters and story lines from J.K. Rowling's intricate fantasy world, hundreds of bands devoted to the Potter experience have formed in recent years.

The genre has its own name (wizard rock) and fashion sensibility (checkered scarves and askew neck ties replicate the Hogwarts school uniform) as well as a do-it-yourself aesthetic (most acts book their own shows).

With a decidedly youthful and literate audience, bands such as Draco and the Malfoys, Tom Riddle and Friends and the Moaning Myrtles are as likely to gig in public libraries, bookstores or church basements as at rock clubs.

But the movement has grown big enough to support its own summer festival circuit. On Memorial Day weekend, more than 300 devotees gathered at a YMCA summer camp lodge in the Ozark foothills for Wrockstock 2008, a wizard rock extravaganza featuring 15 bands over three days.

Later this summer, similar events will happen in New York, Chicago and even De Pere, Wis., near Green Bay.

"A lot of people don't have a lot of friends where they come from," said Leffler, who plans to move to Louisville to join a friend she first met online in a wizard rock discussion forum. "And then they find 200 friends here."

While the band names and lyrics pay homage to Rowling's elaborate fictional universe, the music is all over the map, from pensive singer-songwriters with acoustic guitars to blue-eyed soul and banjo-inflected country.

"People might assume that music based on Harry Potter would be kind of gimmicky and shallow," said Matt Maggiacomo, the one-man band known as the Whomping Willows.

Maggiacomo, 29, is a veteran of the music scene in Providence, R.I. But it wasn't until he found wizard rock that he was able to quit his day job as technical writer and focus on music full time. A crowd of 500 listeners attended his first show.

"This was my first show where everyone was focused on the music," he said. "A lot of times (before), there were 15 people in the crowd, and they were focused on getting drunk, or talking to other people."

The Missouri festival attracted fans from as far away as Scotland, Wales, Quebec, British Columbia and South Africa — many of whom were visiting the country for the first time.

Forget about New York or the Grand Canyon. For those first-time visitors, the wizard rock community is the real attraction, said festival organizer Abby Hupp.

"They come here and have a sense of belonging," she said. "If you see that even total strangers will love you, it changes you. You become a more open, happy person."

At Wrockstock, the music came with a message. The merchandise table not only had concert T-shirts and compact discs, but bracelets calling for an end to genocide in Darfur and literacy-promoting bumper stickers.

As founder of the nonprofit Harry Potter Alliance, Boston resident Andrew Slack taps into the wizard rock world to promote social activism among what he calls the real-world minions of Dumbledore's Army, the Hogwarts School of Witchcraft and Wizardry student group that rose up to fight intolerance and defend the teachings of their wise professor of the same name.

"Literature has in recent decades been a solitary experience," Slack said. "But it can also be a communal one."

For Slack, that means voter registration booths at wizard rock concerts, or fliers alerting the audience to the threat of media consolidation or global warming.

With all seven Potter books now complete, some wizard rock fans fear that the scene could be short-lived.

Yet with three more movies (the seventh and final book will be made into two films) and Florida theme park still on the horizon, most Potter acolytes don't expect the cultural filament to burn out anytime soon.

"I don't think it's going to last forever," said Slack, who didn't read his first Potter book until after graduating from Brandeis University in 2002. "But the Harry Potter fan culture is never really going to go away."