It was the party of the night. For the invited.
Nylon magazine was hosting an "It Girl Prom" at the Gilded Lily on West 15th Street. It promised a cute crowd, open bar and a performance by the Swedish singing duo Icona Pop.
Under the skeptical eye of an outsize bouncer, several iPad-wielding door-girls checked the names of hopeful guests. "Press?" said Terence Edgerson, 26, who was bobbling gently but insistently against these gatekeepers like a housefly trying to get through a glass window.
Charming and a sharply dressed in a black velvet Dior Homme blazer and leopard-print shirt, Mr. Edgerson had all the élan needed to fit into a stylish party — except for one inconvenient detail. He wasn't invited.
But as a veteran party crasher, he was not about to give up. About 20 minutes later, Mr. Edgerson, who identifies himself as a writer for the obscure Bunch magazine and a party chronicler under the Instagram and Twitter handles @NYSocialBee, spotted several acquaintances on their way in. One fellow extended a friendly arm and escorted Mr. Edgerson inside, as a plus-one.
Soon enough, he was slinging back cocktails, air-kissing fellow partygoers and dancing onstage with Aino Jawo, one half of Icona Pop. Flashbulbs popped.
"It was such a blast, I had so much fun," Mr. Edgerson after an hour inside, spilling into the night with an "It Girl" party bag dangling from his arm. But there was barely time to sift through its contents before heading uptown. There were more parties to crash.
New York's private-party scene allows a select few to eat, drink and be entertained for free, often in the company of celebrities. The irony is that while exclusivity is the key to this circuit's appeal, it relies on a constant stream of fresh faces, pushing their way through the velvet rope, to stay vibrant.
Hence the enduring New York social type: the sharp-elbowed dervish party crasher, comprising e qual parts of opportunism, chutzpah and off-price designer clothes, and whose current iteration is exemplified by Mr. Edgerson.
Not everybody is so charmed, of course.
"Party crashers are a publicist's biggest nuisance," said Kelly Brady, owner of Brandsway Creative, a public relations firm that has managed large events for the Daily Front Row and others.
"Our clients hire us to craft the perfect guest list of people for their event, and curate the right crowd for their brand," she wrote in an email. "Party crashers are the ones who act the most entitled a t the door, by trying to pass themselves off as a reporter from some bogus website. And if they do weasel their way into a party, they are the ones who drink too much, follow the trays of passed hors d'oeuvres, and hoard the gift bags at the end of the night."
Ms. Brady's firm maintains a blacklist of about a dozen crashers, mostly men, some of whom falsely claim to be reporters. "Just the ones that have misbehaved, that you don't want back," she added. "A party crasher can get through, and if they blend in, I won't know."
She named one unwelcome fixture on her blacklist, William Gaines, who she said claims he worked at Comcast. She has barred him from her events, but that doesn't always stop him. One time, she said, � ��he showed up before the event and was in the restaurant before we arrived to set up for the opening."
Reached by email, Mr. Gaines said he indeed worked at the Comcast in the mid-2000s and is currently an actor who "receives invitations to events all over New York City and beyond." He added that the restaurant episode is "a figment of that Brandsway employee's imagination. Quite possibly an immature and bitter P.R. girl harboring resentment that I didn't show the interest in her that she showed in me."
The dean of party crashers is arguably Steve Kaplan, a tall, shambling man who has been on the circuit for decades. Nominally a travel writer for Talent in Motion, a magazine based in New Rochelle and published biannually, he is known as Shaggy because of his unkempt curls.
A relatively benign if perennially uninvited presence, Shaggy has been at the party-crashing game for so long that his arrival these days, at least for some publicists, bestows a certain imprimatur. It means the party was worth crashing.
"If he doesn't show up to your party, your party sucks," said Leigh Cherrier, a spokeswoman for Louis Licari, a Fifth Avenue hair salon that gave a party this month attended by Calvin Klein, Donna Karan, Fran Lebowitz, Katie Couric, Sofia Coppola and Sandra Lee.
Shaggy crashed. "I walked up to him and said, 'Sir, thank you so much,' because I felt like, he came, that means my party is a big deal," Mrs. Cherrier said, adding that the only selfie she took that night was with him.
Reached by phone, Mr. Kaplan declined to comment.
Not all crashers end up being embraced. Nancy Kane, a longtime publicist of celebrity events, warns that crashers who get caught can turn vindictive. "Party crashers are like crazy exes," she said. "Very hard to get rid of, once you eject them. They don't forget."
Ms. Kane said she once had to get a restraining order against a crasher, whom she prefers not to name because of his intimidating tactics, after she threw him out of a party. "He ended up waiting for me, and following me to my apartment that night," Ms. Kane said with a shudder.
And in 2012, a crasher by the name of Priyantha De Silva was reportedly sentenced to one-and-a-half to two years in prison for using a fake credit card to pay for a ticket and Prada bag at a fund-raiser.
But not every showdown with a crasher is so fraught. Ms. Kane laughs as she recalled running the door for a downtown Halloween party, hosted by the designer Karl Lagerfeld, in 2005. Tinsley Mortimer, a prominent socialite, came dressed as the cartoon character Rainbow Brite.
"But then, a few minutes after she arrived, another guest, in a puppy dog mask, said she was Tinsley Mortimer," Ms. Kane said. "I said, you have to take off your mask or we won't let you in, and the puppy went running out the door. Then, an hour later, in walks a ghost and says, 'I'm Tinsley Mortimer.' "
Ms. Kane adds: "The crazier the venue, the easier it is to get in, believe it or not. In Cannes, people are always sneaking into Harvey Weinstein's party at the Hôtel du Cap. You can arrive by boat, and once on the lawn, if you're sneaky about it, you can usually wander in."
Fortunately for the crasher on a budget, a boat is not always required. For Mr. Edgerson, crashing is "the least amount of trouble, and the most amount of fun, you can have without doing any harm," he said. "That's half the thrill, that you've managed to get into this party that you weren't invited to."
Back in downtown Manhattan, Mr. Edgerson had left the Nylon party and arrived at the Dream Midtown hotel on West 55th Street, which was celebrating its revamped lobby bar and rooftop lounge, PHD Terrace.
He wasn't on the list, but the hotel drew an older crowd and softly speaking "press" was enough to unhook the velvet rope. (Bunch, "a guide for the daring creative," is based in Los Angeles and has published five issues in three years.)
A native of Rochester Hills, Mich., Mr. Edgerson has been crashing events since moving to New York at age 18. He said he started out interning for Paper magazine, adding that he once lost a job at Idiel Showroom, a fashion distribution and marketing firm, for falling asleep during a trade show. "I'd been out partying too much, so I couldn't stay awake," he said.
His party-crashing night begins with wardrobe selection, where favorite pieces include a Karl Lagerfeld for H&M blazer and a white Dior sweater. "It starts with what you're wearing, but it's also confidence," he said. "If you are planning to get into the party, you can't second-guess yourself."
But even for career crashers, some doors remain tantalizingly out of reach.
"I wouldn't try and get into a Marc Jacobs after-party or show, and KCD is hard-core," he said, referring to the fashion P.R. pow erhouse, known for protecting every dainty soiree like the Empire defending the Death Star. "No one wants to crash a party that KCD is doing. A lot of people I know in fashion joke around about what kind of training they must go through to deny people."
(Rachna Shah, a spokeswoman for KCD, made no effort to dispel that notion. "I cannot disclose our training methods, but let's just say, if you make it out of training camp, you could probably be hired by the Secret Service," she said.)
Others may argue that firms like KCD are not just entitled, but compelled, to exclude crashers. The most elaborate parties can cost millions to produce, and crashers may pose security risks.
But, asked why anyone would want to attend an event at which they were not welcome, Mr. Edgerson seems almost not to understand the question.
"Why not? It's a party, and people are supposed to enjoy themselves," he said. "And if you want to go enjoy yourself, you should go do it."
In the warm air of an autumn night, bathed by the light of nearby Times Square, Mr. Edgerson pronounced himself impressed with the Dream Hotel. Nursing his sixth free cocktail of the night, he said: "The views are great. Midtown is not usually my first destination choice, but now, after seeing it, maybe I will come up here and hang out."
Mr. Edgerson departed around 1:30 a.m., not to go home, but to a party at the Goldbar, a lounge on Broome Street. This time, he said, he was on the list.
