It was go time.

Just after 7 p.m. on Tuesday night, security teams raced across Fifth Avenue with police barricades, closing off one of New York City’s main arteries to traffic. A grand piano was wheeled into position in front of the dark Saks Fifth Avenue facade between 49th and 50th Streets.

And then: Elton John.

Dressed in a teal jacket, red track pants and his signature red-tinted glasses, he waved to the crowd thronging the barricades from the passenger seat of a glowing purple golf cart as it conveyed him to the piano.

He took a seat at the bench as his husband, David Furnish, and his two sons, Zachary, 11, and Elijah, 9, formed a semicircle around him. And then the countdown started.

“5 … 4 … 3 … 2 … 1!”

The black curtains over the six ground-floor windows rose, revealing rocket ships on pistons, kaleidoscopes and a spinning top.

“And you can tell everybody this is your song,” Mr. John, 75, sang, launching into his famous single.

On the limestone facade behind him, miles of bulbs sprang to life, multicolored ribbons of light streaking their way up the neoclassical building, meandering out and blossoming into pinwheels of light, an annual tradition for the department store since 2004. Fireworks shot off the roof in bursts of orange, red and green.

“Happy Christmas, everybody!” Mr. John said.

In an interview before his performance, Mr. John, who grew up gazing at department store holiday windows at his local department store in Harrow in North London and later Harrods and Selfridges with his family, called the tradition a “magical” part of the holiday season.

“I was always so excited to see the new displays each year,” he said. “It was a highlight of Christmastime.”

Saks also made a $1 million donation to the singer’s AIDS Foundation Rocket Fund and co-curated a holiday merchandise collection with Mr. John that includes more than 60 designers, including Gucci, Versace, Valentino and Jason Wu. The collection includes clothing — including tracksuits, of course — shoes, beauty, glasses and accessories.

The annual ornate department store window displays are spectacular — Saks’s light show and windows alone took more than 250 people around 40,000 hours to complete — but they are a dying art. There are now just a handful of department stores in New York City — Saks, Bergdorf Goodman, Macy’s and Bloomingdale’s — that still build the traditional, handcrafted scenes each year.

In interviews, four of the designers who oversaw this year’s department store holiday window displays shared their inspirations, a look inside the production process — which can last as long as nine months — and what Easter eggs to look for.

Bergdorf Goodman

The department store treats the production of its seven holiday windows as a nearly year-round endeavor.

“We never stop working on either dreaming them up, planning them, producing them, installing or maintaining them,” said David Hoey, the senior director of visual presentation at Bergdorf Goodman who has overseen the handmade displays that stretch along Fifth Avenue between 57th and 58th Streets — and around the corner onto 58th Street — for more than 25 years.

Initial sketching begins in February, the beginning of a nine-month process that involves about 100 people and requires 10,000 hours, Mr. Hoey said. This year, the team decided on a theme of “magic in the making,” featuring seven arts and crafts elements — dressmaking, metal craft, mosaic, papier-mâché, paper sculpture, scrapbooking and woodcraft — each paired with a designer, among them Marc Jacobs, Noir Kei Ninomiya and Libertine.

In the mosaic window, a glittering zebra with green stripes, a giraffe with red spots, a gorilla and a polar bear stand alongside an ace of spades playing card and a mannequin wearing a sparkly silver dress by Aliétte. The scrapbooking window is an Alice-in-Wonderland-like, bird’s-eye view of a mannequin in a black top hat, striped suit and red Mary Jane heels, surrounded by hundreds of scrapbooking projects — with a door on the floor.

“The purpose of all of this is to induce aesthetic delirium,” Mr. Hoey said. “You might have to come back two or three times to catch all the details.”

Bloomingdale’s

As you walk down Lexington Avenue near 59th Street, in front of the Bloomingdale’s holiday windows — which this year are stuffed with teddy bears, oversize ornaments and snowmen — the window designers hope to remind you of your youth.

“We want you to feel the windows from the eyes of a child,” said John Klimkowski, the senior director of visual merchandising at Bloomingdale’s, who has been overseeing window design at the retailer for a decade. “And we always add some surprises in that only adults will get.”

For the store’s 150th anniversary, Mr. Klimkowski said the team of more than 65 people, which began the production process in June, focused on iconic Bloomingdale’s elements like the store’s holiday bear, which customers collect from year to year. The creators, which included more than a dozen costumers, branched out from there, adding active elements like a sewing machine with a needle that moves up and down as though stitching the ribbon on the bear’s bow.

“We want to surprise and delight,” Mr. Klimkowski said of the windows, which also feature wrapping paper, champagne glasses and a 3-D camera in the toy workshop. “Any time we can add some action or movement is a plus.”

Macy’s

Tiptoe is back — and she’s gotten a confidence boost.

The spunky blue reindeer made her debut in the windows of the Macy’s flagship store on 34th Street in Herald Square last year in a series of adventures that chronicled her journey of learning to fly. Now — confident in her powers of levitation — she’s traveling to visit friends for the holidays and spend time with them.

“Celebrating the holidays is something we all longed for, especially during the Covid years,” said Manny Urquizo, the national window and campaign director for Macy’s. “This year, we have the opportunity to all be together, and you can see that reflected in Tiptoe’s journey.”

The store’s nine-month design process begins in February and involves hundreds of people, including graphic designers, carpenters, sculptors, puppeteers and electricians. This year’s windows include squirrels tucked inside a Christmas tree, who pass ornaments back and forth on an oversize marble run; a family of polar bears snuggled up in cozy striped sweaters; and a gingerbread house with miniature gumdrops.

There are also some Easter eggs only the designers know about.

“The little Christmas cards hanging in the bear cave are a little nod to my family,” Mr. Urquizo said. “My kids’ names are inside the cards, and people can’t see that, but it’s nice for me to know.”

Saks Fifth Avenue

When you have Elton John helping to curate your holiday window displays, it seems only fitting for one of them to include miniature rockets that shoot up and down.

“We started with the idea of what’s memorable, nostalgic and great about the holidays,” said Andrew Winton, the senior vice president of creative at Saks, who has overseen the holiday displays and light show since 2018. “And then we thought about how we could bring that into the future.”

Though Saks has been doing its annual holiday light show for nearly the past two decades, this year is the first to feature windows that light up from within and interact with the more than 600,000 lights on the building’s facade, which are synchronized to music — a medley of Mr. John’s hits, including “Step Into Christmas,” and “Your Song.”

This year the window displays include kaleidoscopes, a toy top that opens and closes and a marble run — a nod, Mr. Winton said, to Mr. John’s famous colorful, sequined costumes and elaborate sets. The toys, which move in tandem with the hundreds of thousands of individually programmed LED lights and music, are painted in reflective metallic colors that give them a futuristic twist.

“It was lots of late nights trying to make sure those 600,000 lights all work the right way,” Mr. Winton said. “We were up until 3 a.m. trying to troubleshoot and finalize everything.”

He’s looking forward to returning as a spectator.

“You get to listen to the chatter and oohs and ahs,” he said. “You can see people’s reactions and get a sense of the holiday spirit.”