The acorns were the only unexpected guests. It was the night of the annual fall gala known as Two x Two for AIDS and Art, and a red oak stood tall over the tent that welcomed invitees to the North Dallas home of Howard and Cindy Rachofsky. Just as they had for the past thirteen years, the couple had opened their three-story house and backyard for the city’s most anticipated party, a sit-down dinner and art auction whose multimillion-dollar proceeds would benefit both the Dallas Museum of Art and amfAR, an AIDS research foundation. All evening, the stately tree had been releasing its fruit onto sequined and jeweled, bow-tied and boutonniered guests, whose calligraphed place cards inside the tent read names such as Perot, Jones, and Marcus. For anyone in Louboutins, the acorns now scattered outside presented a treacherous walk to the restrooms.

They did not, however, put a dent in the mood. The buzz for this year’s party had begun as far back as April, when news broke that New York artist Richard Phillips, renowned for what critics describe as “hyperrealistic” paintings that are both beautiful and disturbing, had agreed to donate a nearly eight-foot-tall portrait of Lindsay Lohan for the auction. Then word spread that Lee Ufan, the great Korean-born minimalist, was sending a drawing from his wildly popular From Line series—the piece consisting of some short, squiggly lines brushed across a paper canvas.

The excitement continued to grow when Los Angeles artist Elliott Hundley promised Two x Two one of his much-admired collages: Rose, a canvas filled with old photos, magazine scraps, and tiny fabric pieces held in place by hundreds of pins. Dana Schutz, a New Yorker whose flamboyant, colorful work resides in museums worldwide, announced that she would be donating Bra Removal, a painting of a grotesque-looking woman with monkey-like eyes struggling to undress without exposing herself. And Brazilian artist Alexandre da Cunha ordered his gallery to send one of his favorite creations, 1345041010, composed of a green bottle stuck headfirst into a concrete block.

By October 20, the day of the event, a slew of pre-festivities, including a Karl Lagerfeld–themed party to preview the art, had brought the anticipation to a fever pitch. (Guests at that soiree got to pose for photos in white-ponytail wigs and fingerless gloves.) And Two x Two was a sellout: 450 partygoers had paid at least $1,500 each to sip Dom Pérignon, nibble on caviar, feast on Imperial Farm sous-vide calotte de boeuf, and bid against one another on 131 pieces of avant-garde art, including Joel Kyack’s rather curious Let’s Sit on the Porch, It’s Nice Out, a piece featuring a black balloon attached to a white plastic chair; a hose; a beer cooler; and a glass jar, from which poured what looked to be urine.

The Rachofskys had arranged for guests to promenade toward their home—an all-white, 10,000-square-foot cube designed by modernist architect Richard Meier—over a twenty-foot-long carpet made of 100,000 fake rose petals. On the exterior walls of the house shone giant projected images of roses as well as the corporate logo of event sponsor Neiman Marcus. “Perfect, just perfect,” said Cindy as she made one last inspection of the pink-washed tent about an hour before the party. The tent, where the dinner and auction would take place, was entirely camouflaged by boxwoods. Cindy was clad in an ostrich-feather skirt and a pink-satin opera coat, and as she walked among the tables, a few feathers broke free and floated lightly in the air. A few minutes later, Howard, a bespectacled, bearded former hedge-fund wizard, stepped out of the house in an electric-blue tuxedo and a ruffled black shirt. “Those damn acorns keep falling,” noted the 68-year-old to a groundskeeper. Howard looked across the lawn, where hundreds of Kiehl’s goody bags waited to be claimed. Then he stepped onto the fake-petal carpet, testing it out with his patent leather shoes.

Outsiders take great pleasure in describing Dallas as the most culturally hidebound of Texas cities, a paved-over landscape inhabited by staid citizens whose primary concerns are to make money and build big buildings. But perhaps in defiant response to this perception, or perhaps because such a concrete-filled existence demands it, Dallas is also a city of parties—the kind of place where who wore what to the Crystal Charity Ball is every bit as crucial as, say, the most recent report on job growth from the Federal Reserve. So it is only fitting that a party should be largely responsible for making the city what few could have imagined: a bona fide contemporary-art destination. “Two x Two introduced Dallas to new artists,” explains Lucilo Peña, the president of development at the Billingsley Company and a past chairman for the event. “But more important, it has strengthened relationships between collectors in Dallas and the New York galleries. It has made Dallas look good on the international art scene, no question.”

Dallas, in fact, has long been home to some of the country’s most devoted contemporary-art collectors: Raymond Nasher, who filled up NorthPark Center with large-scale sculptures and later built his $70 million namesake museum downtown; Coca-Cola bottling magnate Robert Hoffman, whose affinity for pieces by the likes of Diebenkorn, Twombly, Judd, and Richter led him to build a two-level gallery on his Preston Hollow estate; former Texas Rangers co-owner Rusty Rose and his wife, Deedie, whose taste for the modern is most visibly reflected in their bunker-like, Antoine Predock–designed house in Highland Park; and even Dallas Cowboys owner Jerry Jones, who has championed the efforts of his wife, Gene, to install abstract works in Cowboys Stadium. (One such piece, affixed above a concession stand, is titled—are you ready?—Unexpected Variable Configurations: A Work in Situ.)

And then there’s Howard Rachofsky, the son of a Dallas pawnshop owner. As a young man, his interests were pragmatic: he studied business at the Wharton School, in Philadelphia, and attended law school at the University of Texas at Austin before turning to stock trading. The only reason he walked into an art gallery in Dallas in the early seventies was because he needed something to put on the bare walls of his apartment. He bought some prints by Picasso, Calder, and Matisse, returned to buy a few Abstract Expressionists—and just like that, he was hooked.

Today Howard owns about seven hundred museum-quality works of contemporary art; on any given day, sixty are displayed in his and Cindy’s home, another one hundred are on view at a Dallas warehouse, and the rest are kept in storage or lent out. One of his most recent acquisitions was a sculpture for his front lawn, created by Japanese artist Nobuo Sekine, consisting of a 30,000-pound pink-granite rock installed atop a fifteen-foot-high mirrored base. To startled passersby, it looks as if a giant baked potato is hovering next to the house.

Howard admits he is “almost obsessively driven” to promote contemporary art, an impulse that seems certain to not only secure him a legacy but also transform his city: besides introducing Dallasites to new artists with Two x Two, the Rachofskys—along with the Roses and Hoffman’s widow, Marguerite—have pledged their collection to the Dallas Museum of Art upon their deaths. This means that in another few decades, Dallas will have one of the more important contemporary troves in the world.

Such a feat wasn’t always a given. When the Rachofskys began hosting Two x Two, in 1999, it seemed like a quixotic effort, persuading Dallas society to show up and buy mostly head-scratching art. But Howard and Cindy knew how to throw a party. They brought in celebrities to emcee or perform each year—Sharon Stone, Liza Minnelli, Patti LaBelle, and Dita Von Teese, to name a few—and honored high-profile artists such as Julian Schnabel and Robert Rauschenberg. Before long, stories about the glamorous shindig, and the money being spent at the auction, were the talk of Dallas. Take the 2011 affair: After one of his geometric pieces sold for a staggering $1 million, Los Angeles artist Mark Grotjahn celebrated by drinking way too much Dom Pérignon. He stumbled out of the house, shouting uproariously before collapsing into some greenery next to a parked Rolls-Royce. Alan Peppard, the Dallas Morning News society columnist, pulled out his phone, snapped a shot of the passed-out Grotjahn, and published it on his blog. Almost immediately, Peppard began receiving calls from people asking how they could get into next year’s party.

Those lucky enough to get tickets to 2012’s Two x Two began pulling up to the Rachofskys’ just as the sun was setting. As millionaires and gallery owners, socialites and artists walked up the fake-petal carpet, waiters dressed all in black passed out flutes of Dom and photographers snapped pictures. Young assistants handed out catalogs of the art for sale, which was on display on every wall and table in the house. Guests perused the pieces murmuring phrases such as “stunning” and “timeless” and “that’s really, really interesting.” Deedie Rose scampered about like a frisky teenager, checking on several works she wanted to buy. The silver-haired car dealer John Eagle pondered a sculpture by Dutch artist Mark Manders, Unfired Clay Head. Several women lingered over a display of ten crocodile-skin tote bags that had been painted by ten different artists.

When they weren’t admiring the art, the Two x Two patrons admired one another. To prepare for her first visit, Karla Black, a sculptor from Scotland, had watched reality television shows shot in Dallas, including Most Eligible Dallas and Donna Decorates Dallas. “I thought I’d see more big hair and really red lipstick,” she said in a slightly bewildered voice. “Everyone here is so . . . beautiful.” More than a few men introduced themselves to Maxwell Anderson, the new head of the Dallas Museum of Art, not to say hello to him so much as to ogle his wife, Jacqueline, who was wearing a heroically stretchy silver lamé gown with a Ferragamo fur shrug that, in the words of one observer, did “not come close, thank God, to hiding her cleavage.”

Others wanted to meet Amy Phelan, a curvy former Dallas Cowboys cheerleader who, after leaving the sidelines in the early nineties, had married an investment fund manager, moved to New York, and become a serious art collector. (The Rachofskys named her the event chair of the gala.) She stood in the foyer next to Phillips’s gigantic painting of Lohan, listening intently as Phillips, who looks like a tall version of the actor Hugh Grant, spent five minutes comparing Lohan’s face to that of Norwegian actress Liv Ullmann in an Ingmar Bergman film. “Fantastic,” exclaimed Phelan. “Who would have thought of that?” When someone asked why Phillips had named his painting Lindsay V, he nodded solemnly and replied, “Because I’ve done four paintings of Lindsay already.”

The art was selling fast. Covering one wall was South African photographer Robin Rhode’s series of 21 photographs, hung upside down, of a man playing pool in a run-down pool hall. On a bid sheet, someone had written down $78,000 for them. Someone else had bid $25,000 on a small sculpture by Matt Johnson of a woman bathing in half a watermelon. The woman, oddly, was the same pinkish color as the watermelon flesh. “We could have sold three of those,” said Howard with a shrug. The Lee Ufan drawing of squiggly lines? Someone had bid $34,000 for it. Da Cunha’s green bottle in the concrete block had drawn $8,500. The only thing that had no bid was Kyack’s plastic chair holding the jar with urine-colored liquid. “It’s still early,” said Howard.

Up on the second floor, Suzanne Droese, who runs a PR business, and Blake Stephenson, the publisher of the Dallas edition of Modern Luxury, spent a few minutes discussing the unique challenges of their new hobby as contemporary-art collectors. “My housekeeper mistakenly plucked off a wire hanging from a small mixed-media piece that we bought at another art auction,” said Droese. “Almost ruined the whole thing.”

“We had to place a Lucite case over a sculpture that we bought here last year because our dog did nothing but lick it all day long,” sighed Stephenson.

Soon Houston philanthropist and socialite Becca Cason Thrash arrived, wearing Givenchy and three nearly identical cocktail rings on her right hand—one from an ex-husband, another from an ex-boyfriend, and the third from her present husband. (“I wanted all three of them to feel included!” she declared.) Although Thrash travels the world going to parties, she almost never comes to Dallas except to attend Two x Two. “There’s just no event like this anywhere else,” she said, turning to air-kiss Cerón, the celebrity hairstylist, and his boyfriend, party planner Todd Fiscus. (It is Fiscus who has organized the Two x Two gala for the past twelve years.) “Todd! Cerón! Onward to the tent, you beautiful men!”

Inside the tent, more Dom was poured. As waiters served the food with military precision, actor and singer Alan Cumming, the evening’s performer, took the stage to sing a few bawdy songs he had written, one about the excesses of plastic surgery (“Don’t go to the plastic surgeon anymore. He won’t tell you you look like Zsa Zsa Gabor”). The guests roared with laughter, except for maybe those with face-lifts, who strained to crack a smile. During a break before the auction, everyone flooded the patio outside, where guests air-kissed and gossiped some more as waiters passed around fresh beignets. Heading back to the tent, Cindy was walking by Jacqueline Anderson and socialite Ana Pettus when, suddenly, her heel caught on an acorn. The blond-haired hostess fell back, her ostrich-feather skirt pitching forward. A few men from Neiman Marcus gasped. Women turned politely away. Luckily, Cindy fell into New York actor John Benjamin Hickey, who quickly caught her around the waist. “My boyfriend!” Cindy screamed with a laugh.

“That would not have been good!” Pettus called out to Cindy, as the latter preened her feathers. “You’ve got a lot of work left to do.” Then Pettus slapped Anderson’s yoga-toned behind, cracking the awkward silence with a loud thwack. “Let’s get some art, girl.”

They went back into the tent, where Sotheby’s auctioneer Jamie Niven took the stage to sell the top works of art. The bidding was fast and furious. Hands went up as Niven discussed the significance of Schutz’s woman taking off her bra. Several people—some from out of town, others from Dallas who wanted to remain anonymous—called in their bids over the phone. It was a phone bidder from Philadelphia who won the Schutz piece, for $120,000. A painting by Michaël Borremans of a woman contemplating an egg in her hand went for $180,000. Manders’s head sculpture went for $95,000. The most intense bidding was over a specialty item: a first-class trip to Paris for a photo session with Karl Lagerfeld at his studio. It sold for $125,000 to an older woman who was later overheard explaining that she’d be giving the trip to her daughter as a birthday present.

The opening bid for the Lohan painting, the prized work of the evening, was $200,000, but it quickly became apparent that there weren’t many people ready to commit to having the face of a self-destructive B-movie actress on their wall. A Dallas man calling in by phone—he was at a wedding in another part of the city and had stepped away for a few minutes to listen in on the auction—got the painting for $300,000. Still, one woman in the tent was convinced the man had landed the deal of a lifetime. “If Lindsay Lohan dies anytime soon—car wreck or drug overdose or something—she’s going to be the next Marilyn Monroe, and that painting is going to be worth a ton of money,” she announced to her tablemates.

“Hear, hear!” replied someone at the table. “To Lindsay’s potential demise!”

By the end of the evening, proceeds from the night topped $4.6 million, the second-highest revenue ever for Two x Two (over the years the party has raised more than $40 million). Just about every piece of art had sold except for a few stray items, including, yes, Kyack’s plastic chair and urine jar. “Oh well, you never know,” said Howard. “But I bet no one will ever forget that piece. I always like to stick in something that gives people a little jolt.”

Two x Two’s guests sipped their last drinks and began their goodbyes. As people trickled toward the valet, Phelan, Pettus, and Thrash discussed where to go next. “Oh, the night isn’t over,” Phelan informed her compatriots. “This was just the pre-party.”

Right then, an acorn hit Pettus’s head and rolled off her shiny ponytail. Phelan smiled. “No, the night is not over.”