EXCLUSIVE: If Best Picture was determined by the Boston citizenry, Patriots Day would likely win, going away. On Wednesday evening, CBS Films, Lionsgate, director Peter Berg and Mark Wahlberg and his fellow producers unveiled the drama about the 105 hours that followed the 2013 Boston Marathon bombing. That started with first responders and surgeons battling to save the lives of grievously injured victims, and then became a focused manhunt as federal and local law enforcement moved quickly to identity and neutralize Tamerlan and Dzohkar Tsarnaev. They were the sibling terrorists who planted and detonated homemade bombs at the feet of a crowd rooting on runners at the finished line on Boylston Street.

A ticking-clock procedure thriller grounded by the display of courage by ordinary people in extraordinary circumstances, the film left the Wang Theatre on Tremont Street awash in tears; many of those attending figured prominently in the events displayed onscreen. It is the second cathartic premiere I attended in Boston in the last 12 months, the other being Spotlight before it won the Best Picture Oscar. Boston is a city whose inhabitants are historically defiant by nature, way before the term Tea Party became political rhetoric. At this premiere, the audience applauded but seemed a bit stunned.

'Patriots Day' Special Closing Night Gala film Presentation, AFI Fest, Los Angeles, USA - 17 Nov 2016
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At a post-premiere party, CBS chief Les Moonves held court along with his CBS Films president Terry Press, and the Lionsgate brain trust that included Patrick Wachsberger, Michael Burns and Erik Feig. It was appropriate that Moonves was there; it was a 2014 60 Minutes segment on the Marathon Bombing manhunt that paved the way for cooperation from locals that informed the script Berg wrote with Matt Cook and Joshua Zetumer, from an original by Paul Tamasy & Eric Johnson, Wahlberg’s cohorts in another Boston-based drama, The Fighter.

“I worked with CBS and 60 Minutes on that segment with Scott Pelley and producer Michael Radutzky, and had a very positive experience and trusted them that this would be done right, and there would be no hidden agendas, no trying to make the FBI look bad,” said Richard Deslauriers, the former FBI Special Agent who spearheaded the investigation on the federal level and is played in the film by Kevin Bacon. “The movie was well vetted and they allowed us to make recommendations in the script, and I’m sure they did this with all the major characters. I made very few. The movie came out so well because they really cared about getting it right.”

The post-premiere party was filled with cops like former Boston police chief Ed Davis (played by John Goodman), Watertown officers Sgt Jeffrey Pugliese (J.K. Simmons in the film) and Richard Donahue, race officials, survivors of the bombing, and some of those first responders who consulted on the movie. They looked all the while like ordinary people, but they stood tall when it counted. Like Dr. Jeffrey Kalish, the Boston Medical Center vascular surgeon who was with his kids at the marathon to cheer on his runner wife, and quickly rushed into surgery to help save dozens of the grievously injured bystanders on operating tables.

The place was crawling with the cops, including the ones who cornered the terrorists in Watertown and engaged in a ferocious firefight that has to be seen to be believed, as the terrorists lobbed homemade bombs at local cops, many of whom had never before fired their weapons in the line of duty. Many of the cops play small roles in the film; it would be hard to imagine pro actors would nail that distinctive Boston patter, the kind I usually hear when I wear a Yankees hat at Fenway Park.

Berg, who coordinated all the mayhem, heroism and villainy of that April week into a film that is his high-water mark as a director, was somber at the party and felt the weight of the event. So was Wahlberg. A steady stream came up to them, some who’d just seen for the first time a film that captured the defining moment of their lives. I heard several thank Berg for keeping his word and not sensationalizing or politicizing, as he promised he wouldn’t. This after they risked themselves to give him full cooperation and access that started in scripting the procedural to shooting all over the city. That culminated with filming at the 2016 marathon finish line, including survivor Patrick Downes completing the race three years after the bombing took one of his legs. His wife Jessica Kensky lost both her legs, and their fight for survival is a subplot in the film.

Patriots Day - Special Boston Red Carpet Screening

If Wahlberg and Berg were most in demand of selfies (David Ortiz couldn’t make the party after attending the premiere), a close third had to be Dun “Danny” Meng. He is the remarkable Chinese immigrant who was carjacked by the fleeing terrorists. And who, in a defining moment of courage, escaped the vehicle while the terrorist were gassing up for a trip to New York. Meng quickly gave cops not only a description of the beloved Mercedes he worked so hard to buy, but also its GPS tracking number, and their plans to detonate their remaining bombs in Times Square. I told the soft-spoken Meng, an Internet entrepreneur who lives in Cambridge, that the F-word he uses in the film might be remembered almost as iconically as the one that Red Sox slugger Ortiz defiantly spoke when addressing the Fenway Park crowd in a memorial for the bombing victims.

“I don’t think I actually said it to the cops,” he said humbly, “but Pete Berg asked me what was in my heart, and what was in my heart was “get those motherfu*kers!”

Deslauriers, who now works in corporate security for Roger Penske, said the film closely re-created the painstaking investigation. It wasn’t fun for him to watch: after they found the terrorists in surveillance footage, he, the mayor, governor and Boston police chief agonized over when and how to inform the public and ask their help in identifying the bombers. After the footage was released, MIT Patrol officer Sean Collier was gunned down in his patrol car by the fleeing bombers.

“You think about those victims, and I had tears running down my face,” said Deslauriers, who doesn’t look like a man who cries often. “It brings back a lot of difficult memories. But in the end, our goal was to make sure that no more bombs went off in Boston and no more innocent people were killed. We mourn Sean Collier, but nobody could have foreseen what happened after we released those photos. What we could reasonably foresee happening is that these criminals had more bombs. And given what happened in Watertown on April 18th and 19th, they did have more bombs and they were going to kill more people, most likely in New York City or somewhere between Boston and New York. Our goal was to make sure no bombs went off in this country. We had to find those individuals as fast as we could.”

That decision was made more complex when someone leaked the footage to media. The development accelerated the release of the information, but Deslauriers said it might have contributed to the unexpected tragedy of Collier. “Whoever leaked that information to the media made our jobs harder, just like those three college student down at UMass Dartmouth who were friends of Dzhokar. They destroyed evidence and I had to send 50 FBI agents in hazmat suits, in a teeming rainstorm, to a landfill in Bedford, Massachusetts for two straight days before we found that evidence. If they had come to us earlier and identified the individuals, who knows? Sean Collier might be alive today. We might have captured them earlier if they had just done the right thing and come to us. The movie captured well all of the emotions. We were going on gut instinct and what we thought was the right thing to do. All we knew on that Wednesday and Thursday as we debated what to do with the evidence was that we had three dead innocent people, we had dozens who suffered grievous injuries with amputations and lower body injuries. We had hundreds of injured. We had a terrible terrorist attack in our city. And we knew we had these visual images of these two mad bombers who were out there and who very likely had more bombs in their possession. We had the president coming in for the memorial, and we did not know where these guys were. That was a very stressful period,” he said.