When “Osloopened Off Broadway in the middle of July, it sounded like the opposite of summer popcorn fare. The latest play by J.T. Rogers was a meaty evening, a thinking theatergoer’s chronicle of the back-channel diplomacy that resulted in the Oslo Accords of 1993. It was brainy, it was challenging, and it was three hours long.

But as critics and audiences discovered last summer, “Oslo” is also a political thriller, as gripping as films like “Argo” and “Munich.” Now it’s back, spurred by its Off Broadway success and streamlined down to two acts instead of three, entering the race for the Tony Awards in a production that opens tonight at Lincoln Center Theater’s Vivian Beaumont Theater. In its larger home, the narrative’s world-changing ambitions get amplified — as do the elaborate stage choreographies required to keep “Oslo” propulsive instead of talky.

“It’s harder than any musical I’ve done in there,” said Bartlett Sher, the director who is far better known for his work with classy musical revivals — “The King and I” and “South Pacific,” both produced, like “Oslo,” by LCT in the Beaumont — than he is for straight plays.

“Oslo” has a whopping 64 scenes, telling the globetrotting tale of a real-life Norwegian couple and the risky back channel they created for the top secret, high-stakes peace negotiations between Israel and the Palestinian Liberation Organization that resulted in the 1993 accords. A cast of fourteen actors, led by Jefferson Mays and Jennifer Ehle as the central Norwegians, powers the action in a swirl of shifting furniture on an immaculately spare stage.

“It just never stops,” Sher said of the production. “Every lighting state is so precise. You have to be careful about what everybody sees all the time, because the play is so heavy on the thinking that the audience can’t have any stress about where they should be looking.”

The project originated with Sher, the resident director at LCT. He got to know Terje Rod-Larsen and Mona Juul, the real-life diplomats at the heart of “Oslo,” as fellow parents when their daughters began attending the same Manhattan school. Taken by the stories of political intrigue and hidden statecraft that Rod-Larsen would tell him at their daughters’ soccer games, Sher thought Rogers, the politically-minded playwright with whom Sher had worked on LCT’s 2011 staging of “Blood and Gifts,” might find a play there, and suggested that the writer and the Norwegian meet.

As Sher had suspected he would, Rogers became fascinated by the stories of the Oslo peace accords. “It became a bit of a rabbit hole that I went down,” the playwright admitted. After many interviews and much research, Rogers had come up with one early draft of the play that clocked in at four and a half hours.

Over the course of four years and three workshops, two of which were held at LCT, details were pruned and scenes dropped to get the show down to three acts, each about the length of an episode of bingewatchable TV. On a word by word basis, Rogers, who has to pack a heavy load of information into the drama, crafted his lines down to the comma.

“The point of a line in the last word; the point of a speech is the last sentence,” he said. “I always tell actors to memorize the punctuation, because it’s as important as the words. I’ve tried to create an engine for them.”

Sher likens the script to the language-intensive plays of Shaw. In his office just off the Beaumont lobby, he recalled Ehle’s work on a complicated speech in which her character enumerates a list of questionable actions by the PLO.

“In speech terms, Jennifer had to go through and figure out how to do it in three breaths, and lift through the whole thing so you get a sense of the accumulation of facts,” he said. “It’s where they breathe, it’s emphasizing this word here, this shift in rhythm there, how much faster it can go to here. It’s close to conducting.”

Despite the creative liberties taken by the play, the final result feels authentic, according to the real Rod-Larsen (who’s portrayed in “Oslo” by Mays). “They’ve managed to crystallize into three hours what actually happened in nine months,” he said. “It gives a very true portrait of what happened, though it doesn’t mirror what happened.”

Although the play consists almost entirely of small groups of people talking in rooms, the international scope of the subject and, now, the size of the Beaumont endow the proceedings with a sweeping scale that makes it easy to see why Sher and Rogers are already at work on a film version, currently in development with film and theater producer Marc Platt (“La La Land”). In striving to create a balanced portrait of all sides of the Israeli-Palestinian conflict, as seen through the impartial lens of two Norwegians trying to help — and then acknowledging the ultimate failure of the accords to sustain peace — “Oslo” also creates a space for the public discussion of an explosive issue about which most Americans hold fierce, seemingly unshakable opinions.

“One of the pleasures of this is being able to have conversations about something we don’t know how to have a conversation about,” Sher said.  “There’s no agenda about whose side we’re on. We want to tell the history of that event, so that the people coming in can go from there.”