What happened at Deitch Projects on Saturday night may have signaled the return of giddy decadence, or the collapse of the art world, or the end of civilization as we know it. Whatever it was, it took only an established SoHo art gallery, a Los Angeles-based fashion brand, an international passel of half-naked artists, and some public micturition to pull it off.

To be sure, New York has witnessed every variety of nonsensical, chocolate-splattered performance art by empty-headed poseurs. But if being engaged by art is what matters, it was hard to argue against these pranksters.

Deitch Projects’s intent was to throw a dinner in celebration of the 131 artists photographed by Jason Schmidt for his new book “Artists.” As gallery owner Jeffrey Deitch thought through the options, however, he realized that a formal banquet held no appeal. “For 250 people? It would have been like a political dinner,” he said.

Instead, he invited the Vienna-based ensemble Gelitin to stage “an intervention during dinner.” He added a fashion angle with the evening’s sponsor, Max Azria, which boosted the evening’s glamour quotient.

While a man wearing heavy makeup and rhinestones played a shrill, whining Theremin, seven men with buckets on their heads and drag-queen stilettos on their feet — the four-man Gelitin team along with three Icelandic artists from a collective called Moms — traipsed around a raised platform. During the course of dinner, they built a giant, plywood arch — with several tangents — that spanned the width of the Deitch gallery. The hodgepodge structure, pieces of which had been constructed ahead of time, reached from the stage up and over the midsection of two long rows of banquet tables and was screwed (with a drill) into a high portion of the gallery wall. The tables underneath gave the room an eerie, romantic feeling; each sat nearly 100 people and was dotted with ornate silver candelabra and white lilies.

While the boys worked on what Mr. Deitch called “a live sculpture,” the guests ate, drank, and speculated.

What are they doing?

What if it all falls?

Who would get sued?

This was a strictly adult evening. Among the artists, pants were optional. And a European fascination with exposed genitals prevailed.

The silly costuming, however, took a backseat to countertenor Anthony Roth Costanzo, who climbed the structure and sang “Flow My Tears,” a 16th-century song by John Dowland. As Mr. Costanzo ascended even higher, it was not just suspense that hushed the crowd: the mournful song, beautifully sung, held sway. Still, it was not immediately clear why he risked his life for this project.

“I believe that the future of classical music is in the context,” he said afterward. “Maybe the song touched a few people here who wouldn’t have heard it otherwise.”

One such person may have been the young man wearing a Care Bear on his head. Though he looked like an idiot waiting to get noticed, his level of fascination with the construction project was intense.

Are those beads hanging from their nether regions — or strings, I asked him.

“They’re tool belts. Go look closer,” he said. Dinner guest Casey Spooner — who is half of the band Fischerspooner and was wearing a cape for the evening — split the difference of opinion: “It’s both.”

Mr. Spooner was partially right. The artists had tied bolts to the strings, so that as bolts were needed, they were within reach — as they would be in pockets. Tobias Urban, of Gelitin, had tied the strings to a condom stuffed with a small red potato that served as an anchor, wedged in a rather uncomfortable location. “I still can feel the potato,” Mr. Urban said after the event was complete.

And, yes, there was an end point to this. When the structure was completed, the seven men took their places on the arch. On cue, each one urinated into the bucket on the head of the man below him. It was a fountain. The crowd went wild.

The evening’s activities were ridiculous, but the sculpture did succeed in making an intervention into the eerie, exaggerated dinner party. It will be a long time before a political dinner tops this.

After the construction, the smelly, exhausted troupe talked to curious guests and were brought dinner. Schuyler Maehl, an Icelandic painter wearing white sparkling pantyhose and a pink “I Love New York” tank top, explained that the group was in town until Monday and that though they had worked hard on the details, there was still one question the group had to work out: where to watch the Super Bowl.