Tom Hanks and Meryl Streep in The Post (Niko Tavernise/Twentieth Century Fox)

Concentrating on just a few months in 1971, Steven Spielberg’s absorbing The Post is a First Amendment thriller, centered on the publication of the Department of Defense’s Top Secret “Pentagon Papers.” Even though the real-life outcome is already well known, the film’s rousing success is due to its dual focus on the behind-the-scenes business we didn’t know: the feminist evolution of The Washington Post publisher Katharine Graham (a sterling Meryl Street) and the step-by-step details of how a journalism and legal feat was achieved under the baton of editor Ben Bradlee (Tom Hanks, in his fifth Spielberg starring role). At this time, Bradlee was not yet the national newspaperman who was portrayed by Jason Robards in Alan Pakula’s All the President’s Men (1976), which was about the investigation of the Watergate scandal.

Kay Graham, though, did not appear at all in that film. How could the only woman in charge of a Fortune 500 company be invisible? Inspired by Graham’s Pulitzer Prize–winning memoir, Personal History (1997), Liz Hannah’s original script focused on her evolution from a mother of four, a well-connected Washington socialite, and nervous placeholder at the head of the family business, after her father’s and husband’s deaths. Josh Singer, writer of Spotlight and TV’s The West Wing, expanded the script with broader context.

The ironic introductory bridge between the two story lines is an early crisis: a furious President Nixon bans The Post from his daughter Tricia’s wedding in June due to a catty comment in the paper on his other daughter’s nuptials. (The president’s actual audio tapes are used throughout.) Bradlee meanwhile is putting together clues that The New York Times is working on a Big Story and trying to figure out how to get a piece of the mysterious action.

His boss, Graham, has nervously agreed to the advice of Fritz Beebe (Tracy Letts), chairman of the board of the Washington Post Company, that The Post should go public for financial security. Now in her fifties, Graham has carefully gone over all the facts and figures of budgets and stock prices, but in the face of her all-male board, and the all-male potential investors in New York, she falters and demurs to Fritz in the decision-making. She’s just beginning to trust her own opinions and decisions, like the risk she took in promoting the aggressive Bradlee to raise the national profile of the paper.

Bradlee sees as a challenge The Times scoop on Sunday, June 13th, the first excerpt from “History of U.S. Decision-making in Vietnam, 1945-66,” the Rand Corporation’s academic and tell-all analysis of the doomed U.S. involvement. He leaps at the opportunity when sample pages from the report are anonymously delivered. (In her memoir, Graham says she gave Bradlee a tip from her friend James “Scotty” Reston of The Times.)

She personally felt betrayed by another close friend, ex-Defense Secretary Robert McNamara (Bruce Greenwood), who had commissioned the report; here, she confronts him on how he allowed her son Don—and so many other sons—to serve, and possibly die, for a pyrrhic purpose. As she prepares for the public offering, Graham has a collegial lunch with a competitor, Times managing editor Abe Rosenthal (Michael Stuhlbarg), when word comes that a federal court has agreed to the Nixon administration’s demand to stop The Times’ publication of any more of the 7,000-page report.

Back at The Post, reporter Ben Bagdikian (Bob Odenkirk) digs around from his old days at the Rand Corporation to figure out that Daniel Ellsberg (Matthew Rhys) was the leaker, and he reaches out to him. The roundelay of various and amusing exigencies for dealing with a political hot potato includes rising editorial writer Meg Greenfield (Carrie Coon). She and other top editors gather at Bradlee’s house to sort the unpaginated copies (the page numbers were on the same line as the words “Top Secret” that Ellsberg cut off) and to figure out whiat shocking revelation to print first, even as the newspaper’s lawyer warns of the legal ramifications. Graham, moreover, understands another risk: the underwriters of the public offering have a week to back out if the company is subject to criminal action.

All the pressures come together while Graham is hosting a retirement party in her home. (The elegant caftan she wears, as well as her other 1970’s power outfits, may help costume designer Ann Roth win another Oscar.) While Streep magnificently encapsulates how Graham rose to that occasion, just as beautiful and meaningful to Graham’s fulsome development onscreen is a change-of-pace, loving tête-à-tête with her eldest daughter, writer Lally Weymouth (Alison Brie), as Lally reads to Graham the actual, encouraging note Lally gave her mother after her father’s suicide eight years earlier.

Though any younger audiences may miss specific references, the film is full of touches of verisimilitude, like the actual model of the photocopier Ellsberg used, borrowed from the Xerox Museum, and period typewriters. Only Bradley Whitford’s “Arthur Parsons” is a fictional amalgamation of several corporate naysayers. John Williams’s score is one of the strongest of the 29 he’s created for a Spielberg film, and it helps to unite the disparate components.

The “start the presses” tension—from the copy editing, to the linotype machine set up, on to the reading of the Supreme Court decision, New York Times v. United States—is as much a guaranteed audience pleaser as Mr. Smith Goes to Washington.