Jazz and Cocktails From the Crypt

On the steps of the Church of the Intercession on 155th Street and Broadway, Allison Meier, the senior editor for Atlas Obscura, an online compendium of "the world's wondrous and curious places," was directing small groups of partygoers wearing vintage formalwear into the church, through the cemetery outside, and down into an underground crypt.

"This is the only currently operating cemetery in Manhattan, but they just do immediate burials, meaning that you can't buy a plot—you can only get a spot if you need to be buried right then!" explained Ms. Meier, Atlas Obscura's resident cemetery aficionado, trying in vain to conceal her enthusiasm.

Guests collected inside the crypt on Saturday night, marveling at the majestic architecture and sipping Prohibition-era cocktails as candlelight danced across the walls and a jazz pianist began warming up the crowd. The guests had come for Cocktails in the Crypt, a night of jazz and vintage-inspired libations, put on by the New York Obscura Society, the real-world exploration arm of Atlas Obscura.

"I forwarded the information about this party to my roommate and said, 'I'm dying to go!' She asked me if the pun was intended. It wasn't, but I wished it was," said Anne Johnson, the social media manager for Vogue.com, looking around the crypt.

Ms. Johnson then smiled knowingly while reflecting on the fact that the cemetery only accommodates on-demand burials: "Wouldn't you feel bad if your relative asked to be buried in this cemetery and you couldn't get them in? Like, wouldn't that be so New York? To not be able to get in?"

Dylan Thuras, who founded Atlas Obscura with Joshua Foer in 2009, explained, "This is kind of the natural completion of the mission we started with—we felt like the world was filled with wonders and hidden spots and hidden stories, both far-flung and close to home, so the events we do complete our mission by helping actually bring people to these places."

Megan Roberts, Atlas Obscura's events director, echoed this sentiment: "If you're not looking for new experiences, even within your own city, you're missing out. To us, not only was this an incredible space, but, like…Come uptown for the evening! We were trying to break the mold with this—it's the first event we've done in Harlem."

At around 11 p.m., Loren Schoenberg, the artistic director of the National Jazz Museum in Harlem, descended the staircase into the crypt. As he gazed around in awe, he seemed at a loss for words because of the beauty of the setting.

"How the heck…? Who would think that under a church…?" he said.

A few minutes later, he introduced Lucky Chops, an eight-year-old jazz band whose members were students together at La Guardia High School. The band's set included originals and covers of songs including "Eye of the Tiger," "This Little Light of Mine" and "I Feel Good."

Because of the acoustics in the crypt, the band filled the room with roaring, honking, swinging explosions. Talking was no use. Luckily, guests didn't appear to have come for the conversation—most took the opportunity to show off their finest steps.

Joseph Desmond, the Accounting Policy Director at Citigroup, and his wife Nicole, a Pilates instructor, dressed to the nines (he in black-and-white wingtips, she with a feather in her hair) and dancing with vigor, appeared to have stepped out of "The Great Gatsby."

"When we got married 20 years ago, we took some lessons, and when you're with someone for that long, you start to know their moves. It's important not to step on each other," said Mr. Desmond.

A few feet away, David Bailey and Stephanie Harrison-Bailey, who were married the day before, reflected on Ms. Harrison-Bailey's dress: "It was the first dress I saw on the rack in a thrift store—I got it right before the party," she said.

Mr. Bailey looked closely at the dress.

"I suspect the dress is haunted and being near this crypt will trigger some cataclysmic event," he joked.

By midnight, the air inside the crypt had become humid and taken on the smell of live bodies. Josh Holcomb, the 22-year-old bandleader, wearing wingtips and a vibrant suit, stood outside in the cemetery, taking in some fresh air during the band's break.

"This is definitely the spookiest place we've ever performed—we've never played in a cemetery, much less an indoor cemetery," he said, glancing around at the tombstones.