First things first: What is the Met Gala?

Officially, it’s the Metropolitan Museum of Art Costume Institute benefit, a black-tie extravaganza held the first Monday in May to raise money for the museum’s fashion wing.

Unofficially, it’s the party of the year, the Oscars of the East Coast and “an A.T.M. for the Met” (the last according to the publicist Paul Wilmot). To understand the latter, consider that last year’s event raised $17.4 million — while the Met’s regular old Spring Gala raised just over $2.6 million. How is that possible? What is the secret sauce?

Two words: Anna Wintour. The Vogue editor has been the gala’s chief mastermind since 1999 after first signing on in 1995, and she has turned the event from a run-of-the-mill charity gala into a mega-showcase for Vogue’s view of the world — the ultimate celebrity-power cocktail of famous names from fashion, film, tech, politics, sports and (now) social media. Every brand scratches every other brand’s back.

We think of it as the Fashion X Games or the All-Star Game of Entrances.

When is it?

This year, D-Day is also May Day: Monday, May 1. In theory, the timed arrivals — each guest is allotted a slot — start at 5:30 p.m., usually with the evening’s hosts, and end around 8 p.m. But you try telling Beyoncé when to show up! The most famous generally arrive whenever they want, sometimes as late as 9:30 p.m.

Is there a theme?

The party signals the opening of the Costume Institute’s annual blockbuster show, and the party is usually themed to the exhibition. This year’s show is “Karl Lagerfeld: A Line of Beauty,” a homage to the imagination and creativity of Mr. Lagerfeld, the longtime designer of Chanel, Fendi and his own line, who died in 2019 and helped shape (pun intended) not just the modern wardrobe, but the modern fashion world.

Mr. Lagerfeld famously hated retrospectives — “I don’t want to see all those old dresses,” he once said (he said a lot of things, and often seemed to revel in being politically incorrect) — so this is conceived more as an exploration of his aesthetics.

What about a dress code?

Guests have been instructed to — surprise — dress “in honor of Karl.” Expect to see a lot of Chanel, Fendi and Lagerfeld, as well as Chloé, Balmain and Patou (where Mr. Lagerfeld worked early in his career). Hopefully, that will mean a lot of vintage, which could make this the most sustainable Met Gala ever — an exciting possibility.

Certainly, it will most likely be less costume-y than past themes. (For the “Camp” exhibition in 2019, Billy Porter, dressed as a golden phoenix, was carried in on a litter by six shirtless men; at “Heavenly Bodies” the year before, Rihanna came dressed as the pope.) Still, there may well be a lot of pseudo-Karls. Mr. Lagerfeld, after all, was famous for his personal style, which latterly involved a white powdered ponytail, dark glasses, fingerless leather gloves, black jeans, Hilditch & Key high-collared white shirts and black jackets. Also loads of Chrome Hearts jewelry. (Earlier in his career, before he lost a lot of weight and wrote a diet book, he favored fans; expect a lot of those, too.)

Who are the hosts?

Joining Ms. Wintour as the gala’s co-chairs this year are Penélope Cruz, Michaela Coel, Roger Federer and Dua Lipa. Like the party, the host combo is all about the mix: sports, music, movies. Ms. Cruz has been a Chanel ambassador since 2018. Ms. Wintour, a famous tennis fan and a regular player, is a close friend of Mr. Federer’s. Dua Lipa and Michaela Coel both appeared on the cover of Vogue last year. Plus, they are cool. And Ms. Lipa once performed at the opening of a Chanel store in Shanghai.

Can I go?

Dream on. Unlike other cultural fund-raisers, like the Metropolitan Opera gala or the Frick Collection Young Fellows Ball, the Met Gala is invitation-only, and entry is not just about price — which this year is $50,000 for one ticket, with tables beginning at $300,000 (prices have gone up since last year; inflation!). Qualifications for inclusion have more to do with buzz and achievement (and beauty) — the gospel according to Anna — than money. Ms. Wintour has the final say over every invitation and attendee.

That means that even if you give tons of money to the museum, you won’t necessarily qualify, and even if a company buys a table, it cannot choose everyone who will sit at that table. It must clear any guests with her and Vogue and pray for approval. This year, as in 2022, there are about 400 Chosen Ones, according to a spokeswoman for the Costume Institute.

Who will be there?

The guest list is guarded with the obsessive secrecy of the Illuminati members’ roll until the night itself, but rumor has it Brittney Griner may attend this year. Past and present Chanel ambassadors such as Nicole Kidman, Margot Robbie, Marion Cotillard, Kristen Stewart, Charlotte Casiraghi and Pharrell Williams may well show up.

Designers tend to arrive with famous dates, many of whom happen to be brand ambassadors, which makes the guests walking advertisements for fashion houses as well as for the event itself. Last year, for example, Nicolas Ghesquière of Louis Vuitton women’s wear brought Emma Stone, Jung Ho-yeon, Gemma Chan, Cynthia Erivo, Phoebe Dynevor, Sophie Turner and Joe Jonas. Jeremy Scott, then of Moschino, brought Megan Thee Stallion, Iris Law and Michaela Jaé Rodriguez.

For a moment, a rumor circulated that the Kardashians had not been invited this year, but that turned out not to be true, and odds are Kim will make an entrance. Her decision last year to starve herself to fit into Marilyn Monroe’s famous “Happy Birthday, Mr. President” dress became the controversy of the night, which raises the stakes around her appearance this time around.

How can I watch?

Some stalwart fans line up on Fifth Avenue behind sidewalk barriers and security officers across from the (tented) museum steps, hoping to catch a glimpse of their favorite celebrities as they emerge from their black vans and town cars, but Vogue keeps a tight leash on the livestream (no “Live From E!” for the Met red carpet), and this is not a moment for the rabble. You get a better view from your small screen or computer. We’ll be live-blogging the arrivals, so tune in here.