With Patriots Day, director Peter Berg set out to honor Boston’s heroes by retelling the events of the 2013 Boston Marathon bombing – a day still echoing through the minds of all involved.
While Berg sought a faithful narrative with pinpoint accuracy, the attack itself could not be recreated within the city of Boston. That's where ZERO came in – the Boston-based team was tasked with rebuilding its hometown so convincingly that even locals couldn’t tell the difference.
Although the events of 15 April 2013 are mired in violence and heartbreak, Berg's intent was to tell the other side of the story: how Boston responded in the wake of the attack.
"Pete wanted to tell the story of triumph and love, and a city coming together—not the tragedy," explains Sean Devereaux, ZERO’s Creative Director. "That being said, we needed to show the tragedy itself in order to establish that narrative, and show what people overcame on that day.”
Berg was laser-focused on presenting events with utmost accuracy, which meant avoiding any sensationalization, and considering each detail down to its smallest element. The director wanted the events of Patriot Days to look and feel exactly like the real thing. However, practical effects were out of the question.
"To have special effects or fake bombs put in that same location again was simply not something we would ever consider," says Devereaux. "At the same time, we didn't want anyone to know that we didn't shoot on location, out of that same respect; we wanted to make sure that the movie told the true story.
Berg and ZERO worked meticulously to recreate a digital Boston down to the smallest nuances of the city, studying news footage, smartphone videos, photographs, and anything they could gather from the actual events.
From there, we built a digital city from the ground up: buildings, trees, runners, first responders, street signs, debris, and Gatorade cups. Every detail was considered, down to how much smoke hung in the air, and how the flags blew that day.
"We spent eight months just building our digital city, so that we could put our cameras anywhere and the production could capture any shot they wanted," says Devereaux.
"You could look at a building from a half mile away, or you could look at that same building and that same shot from inches away: the detail and texture and geometry of all of that was part of that build.
ZERO worked closely with production designer Tom Duffield, Matt Kutcher's special effects team, and cinematographer Tobias Schliessler. A small section of the city near the finish line on Boylston Street was built as a small set an hour outside of Boston, with the rest of the set wrapped in green screen as a canvas for ZERO’s digital city. The result was a seamless and respectful tribute to the real Boston.
Building four million digital square feet of Boston was no small accomplishment, but it wasn't just for show—Berg needed the flexibility to move the camera anywhere within the setting, use several cameras in a scene as needed, and swap between different focal lengths. The digital set had to look perfect from every angle, while allowing full freedom of camera movement.
"The way Pete shoots is very documentary-style. We didn't have one line get set, and then cut and do it again; we had 20-minute-long takes where the entire action was captured in-camera, by seven different cameras," says Devereaux. "Shots contained everything from high up in a scissor lift, down to following Mark Wahlberg running through the streets.
"From a visual effects standpoint, to allow the filmmaker that kind of flexibility requires an immense amount of focus – not to mention trust with the director to know that, no matter where you put your camera, we are going to put a photo-real city behind you," he continues. "Some shots have a little sliver of real Boston, but other shots are almost entirely digital."
ZERO's Los Angeles studio helped support the Boston team, with senior FX artists on the west coast creating various simulation-driven effects.
For the home team, meanwhile, proximity to the real-life locations and events proved an invaluable resource. Having hundreds of hours of reference footage and more than a terabyte of still photos were one thing, but being able to step foot outside and see the street itself – just a few blocks away – made a big difference.
"When we have dailies and we're looking at shots, and we were questioning the reality of it, the whole crew would get up and walk down the street to the finish line," says Devereaux. "We'd look from where the camera is and we'd say, ‘What are we seeing? What are we missing?’ We did that constantly throughout."
Devereaux readily admits that the team brought a "healthy nervousness" to the project, tasked with recreating a city that is instantly recognizable all over the world.
Devereaux adds that the project led to some "tough conversations" within the team at first, given their proximity to the events and the real-life tragedy that still touches so many people. But thanks to a close working relationship with Berg, who visited the office frequently during production, they were quickly convinced of his intent for and approach to the project.
"By the end of it, we all respected not only Peter, but also what he was trying to do. We really were onboard for that," says Devereaux. "I'm really proud of that."
Although ZERO's work reached some 600 shots, most viewers will not realize that Patriots Day was digitally augmented. Between Berg's vision for precise realism and ZERO's expert execution, digital Boston looks exactly like the real thing.
"We could show this film right now to an audience member that knows that street like they know the back of their hand, and there wouldn't even be a second guess that it wasn't shot on the street," Devereaux asserts. "It is the most seamless project that we've done to date."