It’s difficult for Gary Souza to return to your garden variety bottlerockets and sparklers after a day at work.

“Over the years, people always say, ‘Oh you work in the fireworks business! You must have all kinds of fireworks in your backyard.’ It’s kind of the last thing we want to do,” he tells Popular Science.

It’s somewhat ironic but understandable, since the Souza family name is synonymous with pyrotechnic wizardry. Their company Pyro Spectaculars dates back to the early 1900s, when Manuel de Sousa immigrated to San Francisco from the Azores. There, he started building his own fireworks for local Portuguese community festivals, while teaching his family the trade secrets. Armed with the patriarch’s own pyrotechnic “cookbook,” ensuing generations of the Souza family (now with a “z”) have since expanded the business into one of the world’s leading firework show organizers. Every year, Pyro Spectaculars now oversees hundreds of performances for holidays, sports events, and concerts, as well as plenty of explosions for Hollywood. Undeniably one of their biggest and most watched events, however, is the Macy’s 4th of July Fireworks Show seen millions of people each summer.

Testing in the Mojave desert

In the weeks leading up to the holiday, Gary Souza and around 60 fellow pyrotechnicans are focused entirely on finalizing the 49th annual Macy’s show. But they are not strolling along the Brooklyn Bridge where it will take place, nor are they balancing aboard one of the four barges in the East River that will supply additional launch points.

“When we do our tests, we go up to a dry lakebed in the Mojave area and just kind of have the whole place to ourselves,” he explains against a brilliantly blue desert sky. “My grandfather, my uncle, my father, my family and kids—they’re all out here for this show. We’re all out here working.This is just something that gets in your blood.”

Souza’s team has spent months designing, planning, and amassing the explosives needed for the nation’s largest July 4th celebration. The 25-minute show is choreographed and timed down to the hundredth of a second, this year against musical arrangements from Ahmir “Questlove” Thompson. However, before showtime, Souza begins at a much simpler starting point.

“For me, honestly, I do it with a pen,” he says. “I’ll literally etch out each song and their sequences and segments. I may put some color markers on there just to know what colorations are happening throughout the show. I put big Post-Its along my wall of the entire show, and add these images and photographs and renderings that we have.”

Once he finalizes the sequences, Souza’s team enters all the data into their design system to sync with the show’s soundtrack. From there, he can generate visualizations of each shell for the performance—all 80,000 of them.

“With the more modern era of this, we’re able to get a three-dimensional video [simulation] of the show and see how that all ties together—what angles should we place the fireworks so that they don’t step on each other,” he says.

New additions for 2025

Certain elements in the Macy’s show are a given. The “Golden Mile” finale feature that spans the entire Brooklyn Bridge is a longtime fan favorite, and Souza’s team has its setup and execution essentially memorized. Some new pieces are another story.

“The actual firework shells are procured from the finest of designers and manufacturers around the world. They tend to be way more consistent and reliable in their duration, timing, brilliance, effect,” says Souza. “It definitely makes it a bit easier on our part with what the show looks like.”

But unlike your bargain firework tent bundles, organizers don’t have many extra rounds to spare for their ultra-expensive rigs. Macy’s organizers wouldn’t cite a specific price point for the show, instead preferring to call it a “gift to America.”

“The cost for it is not a real area of focus for us,” Will Coss, Macy’s Branded Entertainment executive producer and vice president, tells Popular Science.

While it varies by design, Souza estimates that any addition to the show usually receives around three test launches out in the Mojave to assess details like launch speed, height, and duration. Those new elements made specifically for the 2025 show include a 1,400-foot waterfall custom-made in Portugal that will cascade from underneath the bridge. But one design is particularly special for Souza this year.

“One is going to be a yellow strobing cascade that will slowly fall, twinkling towards the water at 1,600 feet wide. That’s something I’ve been working on for 10 years,” he says. “We’ve done a red and white one, and a solid red. We’ve done something in a rainbow, but I’ve [always] wanted something in a lemon or lime sparkling effect.”

‘Bigger and better’

While Souza and crew are wrapping up in the Mojave, a separate team spends about two weeks in New York City prepping for the big night. The tens of thousands of effects each require their own unique position on the bridge and barges—a number that couldn’t possibly be individually ignited by hand. Luckily, the days of lighting matches are long gone for Souza’s experts.

“Forty years ago when we first started to do the Macy’s show, we were the first to bring on electronic firing gear,” he says. “[Today] we’ve got miles of wires and connections and junctions. The bridge has over 240 different firing locations, 12 computers synching it all together.”

Even all of the required electronic rigging has evolved. This year will feature a new firing system capable of launching shells at a faster pace than ever, as well as additions to allow for horizontal launches from the bridge, instead of just vertical ignitions. The 49th annual show also marks the first time that Macy’s will incorporate video projection mapping on the Brooklyn Bridge’s east and west towers, providing the production with extra accompanying imagery.

Despite months of meticulous planning, there will always be uncontrollable variables that require monitoring.. Rain is still a concern, but most of today’s professional fireworks are now relatively weather resistant.

“Wind is always a thing that we need to take into consideration. We work with the City of New York and the fire department to measure the velocity of the wind at the time of the show,” Souza says, adding that they also work with the fire department’s explosives unit to coordinate safety zones throughout the show space.

But even after all of the prep, only one thing matters when millions of eyes are on Gotham this 4th of July.

“It’s really a yearlong process, just figuring out what would be the best way to make this bigger and better than last time,” says Souza.

 

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