IF YOU GO

Ghosts of Hollywood: A Halloween Event

Fundraiser for Jerusalem House open to guests 21 and up, features open bar, complimentary catered food, costume contest and raffle (prizes include a week’s stay at a beachfront condo in Pensacola, an “instant” wine cellar and more). 8 p.m. - midnight Friday. $60-$350. The Foundry at Puritan Mill, 916 Joseph E. Lowery Blvd., Atlanta. 404-350-0513, www.jerusalemhouse.org/halloween

Martinis & IMAX Fright Night

Halloween-themed gathering for guests 21 and older features live music by Frankenfunk, Cosmopositives (as in O-positive) and other special cocktails, screenings of “A Nightmare on Elm Street” at 8 p.m. and 10 p.m. and a costume contest (registration required from 7 p.m to 9:30 p.m). 6:30 p.m. - 11 p.m. Friday. $7 (cover charge only for non-members, free for members) to $8 (cover and movie admission for members and non-members). Fernbank Museum of Natural History, 767 Clifton Road, NE, Atlanta. 404-929-6400, www.fernbankmuseum.org (advance ticket purchase strongly recommended)

Groupon Presents Cobwebs & Cocktails at Zoo Atlanta

Fundraiser for the zoo features open to guests 21 and up features live entertainment, “nocturnal animal encounters,” food and special cocktails, all taking place in the “Spider’s Lair.” 7 p.m.-11 p.m. Saturday. Tickets include admission and two drink tickets, $45 (single), $80 (two tickets). 800 Cherokee Ave. SE, Atlanta. 404-624-WILD, www.zooatlanta.org.

The 1st Annual Dead Man’s Costume Ball

Marietta-Cobb Museum of Art hosts party for guests 21 and up to include costume contest, palm reader, live music, art history trivia, photo booth, full cash bar, hors d’oeuvres and more. 7 p.m.-11 p.m. Saturday. $8 (members)-$15. 30 Atlanta Rd., Marietta. 770-528-1444, www.mariettacobbartmuseum.org.

Spooktacular II: A Halloween Party to Benefit the Museum of Contemporary Art of Georgia

Sponsored by Wilmington Trust, party for guests 21 and up features live music and costume contest, with prizes awarded for most artistic, most audacious and more (costumes not required to attend). All food and drink included in ticket. In addition, guests will be able to take in the 2011-2012 Working Artist Project, “Brian Detter: Elemental,” which just opened at MOCA. 6 p.m.-9 p.m. Sunday. $100. 75 Bennett Street, Suite A2, Atlanta. 404-367-8700, www.mocaga.org.

Maybe we grownups just long to be mistaken for Honey Boo Boo for one night.

Or maybe — just maybe — Halloween is becoming the new New Year’s Eve, a time for otherwise sensible adults to get their party on.

By getting their costumes on.

“It’s just the one time of year you get to be something else, with no drawbacks,” laughed Emily Ryals, 26. “Instead of feeling like a fool by yourself, you get to feel like a fool along with everyone else!”

As the founder of Charter, the new young patrons group (ages 21 to 40) at the Marietta-Cobb Museum of Art, Ryals is hoping to use Halloween’s growing adult appeal to attract new attention and faces (masked, of course) to the fine arts museum located just off the Marietta Square on Saturday night. That’s when MCMA will host “The 1st Annual Dead Man’s Costume Ball,” temporarily transforming its century old Classical Revival building into a spooky, spoofy spot where revelers ages 21 and up can enjoy a costume contest, sophisticated cocktails and “horror d’oeuvres.”

While the idea of people dressed like Freddy Krueger or Snooki sharing the same space as pricey portraits and plein air landscapes might sound kind of "out there," it's actually part of a growing trend. The National Retail Federation says Americans will spend $1.1 billion on children's costumes this year. That's compared to $1.4 billion on adult costumes.

At Zoo Atlanta, they’re expecting between between 1,000 and 1,500 guests Saturday night at the first adult Halloween party held there in more than a decade.

“We’d like all the guests to come in costume,” enthused Keisha Hines, director of communications for the zoo. “That’s the biggest thing about Halloween, right?”

It is now. This weekend will be as overflowing with grownup costume parties as a kid’s candy bag after a trick-or-treating all-nighter. A number are at cultural insitutions like The Museum of Contemporary Art of Georgia and the Fernbank Museum of Natural History. Some are being staged for the first time or the first time in recent memory, as in the case of Saturday’s “Cobwebs & Cocktails at Zoo Atlanta.”

“Halloween is just the perfect event to do something grownup and fun,” said Hines, who hints even a few non-human guests could show up at the party, to be held in a giant tent resembling a spider’s lair (the zoo is home to a few tarantulas, we’re just sayin’). Soon after the popular kid-oriented family festival, “Boo at the Zoo,” wraps up Saturday at 3 p.m., Hines said, “You can have your own Halloween as an adult later that night.”

And you can do it with a clear conscience, since it’s a fundraiser. So is Friday night’s elaborate “Ghosts of Halloween” benefit for Jerusalem House, the Atlanta non-profit that provides permanent housing for low-income and homeless individuals and families affected by HIV and AIDS. Partygoers will get to have their orange-and-black frosted cake and eat it too.

Having a fundraising focus, as many of these newer events do, tends to weed out partygoers for whom an “adult” Halloween party still means pulling on a kitty-cat costume and hitting the nearest bar.

“You have to be 21 to attend, which I think is another reason adults like Halloween parties like this,” said Jon Santos, director of development for Jerusalem House.

Now in its 13th year, Jerusalem House’s Halloween fundraiser is known for the creativity and friendly competitiveness of its costume contest. Santos, who’ll deck himself out as Mama Cass this year — right down to a replica of the ham sandwich that supposedly led to the singer’s demise — is expecting a clutch of faux Honey Boo Boo’s to show up. He’s also expecting some guests who could best be described as “costume shy.” For them, there’ll be the option of purchasing one of the homemade masks created by the children of Jerusalem House’s family program.

Ticket sales are currently running ahead of this time last year, Santos said. That could be due to the improving economy.

But it could also be due to the growing lure of grownups getting to wear costumes for one socially acceptable night. At the Marietta-Cobb Museum of Art, for instance, Saturday’s “Dead Man’s Costume Ball” is the kickoff event for Charter, but adults of all ages are welcome.

Many haven’t needed to be asked twice.

"A lot of our older members are so into Halloween," marvelled Ryals. "A lot of the empty nesters, they're not dealing with their kids anymore and they can't wait to dress up. One lady in particular has already told me — she's making her costume herself, and she's going to win."