“Parkland,” Peter Landesman’s new film about the immediate aftermath of the assassination of President John F. Kennedy, starts off like the greatest episode of “ER” and ends like a Samuel Beckett play. It’s both a thriller that tells a familiar chapter of history in an incredibly original way and a tragedy of immensely personal dimensions.

“I’m obsessed by procedures. And especially when there’s no procedure,” Landesman, a former reporter for The New York Times, told CQ Roll Call.

And when the president of the United States is wheeled into your emergency room with a gunshot wound to the head, procedure goes out the window. “When chaos and fear reign, any plans that did exist, any structure that did exist, all that goes away,” Landesman added.

“Someone please tell me what’s next,” Dr. Malcolm Perry, played by Colin Hanks, says in the film after the president is declared dead. For Perry, who worked to save Kennedy with another physician, Jim Carrico, played by Zac Efron, there was no clear answer. That comes through loud and clear in the movie, as the Secret Service tries to determine its next move and the Dallas coroner gets into a jurisdictional fight with White House staff over custody of Kennedy’s body.

That focus on logistics makes “Parkland” — named after Parkland Memorial Hospital where Kennedy was rushed after being shot on Nov. 22, 1963 — hum along at a breakneck pace.

It follows the first responders, Secret Service agents, FBI agents, journalists, witnesses and even the family of Lee Harvey Oswald on that day and the days that followed. It’s based on Vincent Bugliosi’s 2008 book, “Four Days in November: The Assassination of President John F. Kennedy.”

Navigating the Record

The director was turned on to Bugliosi’s work by Tom Hanks, for whom Landesman had written a screenplay on Watergate. After he read the book, his reporter instincts took over, sending him on a three-year odyssey during which he followed up with as many of the principals as were still alive, such as FBI Special Agent James Hosty, who is played in the movie by Ron Livingston.

Hosty, part of the FBI’s Dallas field office, had kept tabs on Oswald but regarded him as a crackpot. When his superiors find out he might have been the last law enforcement officer in contact with Oswald before Kennedy is shot, they are livid, and he is ordered to destroy the case file detailing his tracking of Oswald, an event depicted in the movie and about which Hosty testified to Congress years later.

Hosty eventually transferred to the Kansas City, Mo., field office. He died there in 2011, but not before Landesman spoke to him as part of his research.

It’s not just the attentive detail to the emergency medical and law enforcement angles that propel the movie. Paul Giamatti plays a shattered Abraham Zapruder, the Dallas dressmaker who inadvertently provided the iconic film record of the assassination as it played out in real time. Zapruder’s attempt to work with the Secret Service to safely process the film shows how nothing was simple that day.

In Landesman’s hands, even developing film is a harrowing journey, fraught with peril.

It’s also about as far from the conspiracy theories surrounding Kennedy’s slaying as one can get, yet it’s just as compelling.

Landesman described Bugliosi’s book as “a blueprint of data” that set his course.

“I became obsessed and went on kind of a three-year journey of investigating, uncovering, shining a light, finding documents, finding interviews. Nothing classified, nothing spooky, nothing Oliver Stoney, and just shit that no one was paying attention to, and realized: We are missing the real story the whole time. We’re missing the more potent, the more authentic and, frankly, the more shocking story, which also happens to be the truth.”

Landesman’s journey from journalism to filmmaking was an “organic” process, he said. He was a painter, “before I was any kind of writer,” and he always knew he wanted to eventually make films. The Watergate screenplay he wrote for Tom Hanks’ production company obviously opened doors, and he sees the skills he learned in journalism as key to his path.

“The reporting I did as a journalist was really heavy. And really dark. … There aren’t a lot of places I haven’t been, both in terms of human nature and geographically, and I think that gives me, it gave me, kind of credibility with the cast and with the financiers,” he said.

Bringing Out the Dead

Once the medical and law enforcement emergencies passed, in both real life and the film, it was time to take stock and to bury the dead. Oswald was killed by Jack Ruby on Nov. 24, 1963, and he died at virtually the same time of day as Kennedy at, of all places, Parkland.

The president and Oswald were also buried around the same time on the same day, but halfway across the country from one another and under much different circumstances.

The film focuses on the Oswald funeral. In doing so, it firmly lays the weight of the story on Oswald’s brother Robert, played by James Badge Dale.

After all the horror and shock of the days past, Robert simply tries to bury his brother with dignity, something that won’t come easily.

The funeral is a scene of immense pathos, and the flat light and pitch-perfect acting of Dale carry the viewer to a place that is unpredictable, slightly uncomfortable and absolutely original.

The real Robert Oswald still lives in Dallas and is in his eighties.

“He was the American everyman,” Landesman said. “You know, he has two kids, he has a dog, he has a wife. He has a split-level house. He goes to a brick company where he’s an accountant, a paper pusher. I mean, the guy is a C student in life if there ever was one. And then, suddenly, he realizes his brother’s the devil. And so what happened to him, happened to us.”

The film doesn’t indulge theories of a conspiracy to kill Kennedy. To Landesman, his film is about something else.

When it ends, with a blurred fade at a funeral for a reviled man, it’s about death and the living who are left behind. It’s a story that was there all along but is just now being told in such a way.

“Parkland” opens Friday at the West End Theater (2301 M St. NW), the Angelika Film Center Mosaic (2911 District Ave., Fairfax, Va.) and Bow Tie Reston Town Center (11940 Market St., Reston, Va.)