NEW YORK -- If you're in midtown Manhattan late next month and see women in green makeup or folks strutting around in colonial outfits, fear not. They're attending the inaugural fan convention for Broadway.

The three-day BroadwayCon -- sort of like a Comic Con for thespians -- promises to connect theatre fans with stage stars, but also wants them to leave with more than an autograph.

There will be meet-ups for fans of Andrew Lloyd Webber or Stephen Sondheim and one for theatre fans who have tattoos. There will be panels about sound and costume design. "Cosplay With the Pros" will features tips from Broadway costumers.

The casts of "Rent," "Fun Home" and "Hamilton" will talk about their shows. There will be a seminar on producing and plenty of master classes led by veterans. There will be sing-alongs, a game show and a cabaret.

The event was conceived by Melissa Anelli and Stephanie Dornhelm, who co-founded and lead GeekyCon, and the original "Rent" star Anthony Rapp. They've partnered with Playbill and the convention will be held Jan. 22-24 at the New York Hilton Midtown.

Although the Broadway community does have gatherings throughout the year -- benefit shows, a flea market and fundraising concerts -- it hasn't had a full-on convention until now.

Enter the masterminds of GeekyCon, which grew from a love of Harry Potter to one of the largest and most recognized conventions for fans of fantasy films, television shows and young adult books.

"I think and I hope it's going to help people really understand why fandom and passion is so powerful," said Anelli. "Passion has been nothing but amazing in our world, so I'm excited for the Broadway world to discover it."

The BroadwayCon lineup is constantly being updated, but some of the stars slated to appear include Lin-Manuel Miranda and the cast of "Hamilton," Jeremy Jordan, Michael Cerveris, Alice Ripley, James Monroe Iglehart, Billy Porter, Melissa Errico, Gavin Creel, Seth Rudetsky, Kerry Butler and Christian Borle and Brian d'Arcy James from "Something Rotten!"

Anelli, who was such a passionate fan of "Rent" that she slept outside its Broadway home at age 16 and eventually befriended Rapp, said BroadwayCon will attract at least two large groups of fans.

"One is the one who heard the word BroadwayCon and said, 'Move all of my cast albums out of the way so I can get to my computer to buy a ticket,"' she said.

"And then you have the 'Next to Normal' fans, the 'Rent' fans, the 'Wicked' fans -- the ones that were brought in by one very specific fan base."

Tickets start at $50 and go up to a general pass with full access to everything on offer for $250. Ten per cent of all profits go to Broadway Cares/Equity Fights AIDS.

Anelli said about half the several thousand expected attendees are under age 30, 80 per cent are from outside the state and 80 per cent are women, reflecting the Broadway audience. Attendees will likely give a boost to Broadway box offices during a traditionally slow month.

Organizers balked at some traditional convention staples, particularly the fees charged for autographs and selfies with stars. "All fans do all day is stand in lines. It feels like a waste of their talent and the fans' energy," Anelli said. "We wanted to make sure it was content-based."

At BroadwayCon, there's no charge for autographs, though fans may have to enter lotteries. Master classes in vocal technique -- with performers from "If/Then," "Rent" and "The Book of Mormon" -- are free, but require registration and fill up fast.

Rapp, currently touring with "If/Then" and who will be present as "Rent" cast members celebrate the show's 20th anniversary, praised his fellow organizers for trying to create a grassroots, homegrown feeling to the gathering.

"So many things have gotten so focused-grouped and corporatized in our entertainment world, and I promise you this is not going to be that," said Rapp, who will be hosting his own master class.

To that end, organizers encourage fans to show up in costumes of their favourite show.

"The idea of being very specifically a fan of one thing is suddenly OK," Anelli said. "It's becoming cooler to be a fan, and I think people are more out there about what they love."