Big speeches rife with “the F-word”– “fascism” — pack the third act of “Keeper of the Flame,” a mid-WWII MGM thriller that was a tad too anti-fascist for fat cat studio chief Louis B. Mayer. Those speeches also burden a film whose third act is perfunctory and clumsy when much of what’s preceded it crackles with wit, intrigue and a civics lesson that doesn’t play like a lecture.

The second ever Tracy/Hepburn picture bombed at the box office, earned indifferent reviews and an even worse “review” from Mayer. He stormed out of the premiere.

But Oscar winner Donald Ogden Stewart (“The Philadelphia Story,” “An Affair to Remember”) considered this his best screenplay. Working from a just-published I.A.R. Wiley novel, Stewart squeezed “The Front Page” in, with “Meet John Doe” messaging and “Citizen Kane” flourishes (Welles’ masterpiece premiered one year before “Flame”).

And director George Cukor — who, like Hepburn, was cool on the project — produced a soundstage-set marvel that has aged better than anyone would have dreamed back then.

Viewed, listened to and quoted today, “Keeper of the Flame” plays like an undelivered indictment, damning and cautionary, and a movie that speaks to America’s present moment every bit as loudly as it did back in 1942-43.

It’s a tale of a heroic, charismatic and cultish public figure, a sort of Charles Lindbergh with Sergeant York’s combat credentials. Robert Forrest dies in a car crash. Spencer Tracy is the veteran correspondant who worked the Nazi Germany beat who now wants to write “The Robert Forrest Story” “so that people will still hear his voice.” Katharine Hepburn is the Great Man’s widow who isn’t so sure that’s a good thing.

Forrest was almost nominated to run for president, a man who inspired nationwide “Forward America” “Americanism” clubs, including the uniformed Robert Forrest Boys Army for America out to displace the Boy Scouts. He died driving off a bridge on his large private estate, because he moved in monied, influential circles.

All the red flags — or baseball cap — warning signs are there. All the celebrated Steve O’Malley has to do is get close enough to the widow to discover “the truth.”

“It’s a pity how easily people are fooled.”

The wisdom of cabbies, country doctors and skeptical fellow reporters is embraced and celebrated.

“Some people don’t fully appreciate the importance of newspapermen as public servants.”

Ah, but to his peers and competitors, O’Malley might not be the ink-stained savior he’s built up to be.

“Oh, he’s a journalist, not a newspaperman!”

A “Kane” styled montage covers the car wreck and press coverage of the unseen/unheard Forrest, ending with O’Malley’s arrival in the press scrum covering this famous figure’s funeral.

Audrey Christie plays an old crush, also on the story, cracking wise about all “Joshua (O’Malley) has to do is blow his horn” and the widow Forrest’s “walls of Jericho” (her silence) will come tumbling down. Stephen McNally plays an even more recognizable “type,” Freddie — the against-the-grain reporter who doesn’t “do” hero worship and is the wiser for it.

O’Malley finds a weeping child (young Dwayne Hickman, decades before “The Many Loves of Dobie Gillis”) who blames himself for his idol’s demise. He runs into an unpleasant, ne’er do well relative (Forrest Tucker), a worshipful hotel clerk (Donald Meek), an embittered employee (Howard Da Silva), a doubting doctor (Frank Craven) and a droll and chatty cabbie named Orion Peabody (Percy Kilbride).

“There’s always good and evil, up against each other,” Orion opines. “A man’s gotta take sides, sooner or later.”

Whatever the embarassment of riches in the supporting cast, we aren’t allowed much time away from our leads, with a reporter turned fan turned would-be suitor who wants to “protect” the widow, because he doesn’t see how she and Forrest’s fanboy private secretary (Richard Whorf) are whispering about manipulating him and burning Forrest’s papers as fast as they can round up some matches.

Tracy is the stoic he needs O’Malley to be, and Hepburn the smart cookie who skips between staying one step ahead of the snooping reporter, and one step behind him.

The plot never wholly unravels, but the logical lapses trigger abrupt turns of the third act, and invite long speeches about great wealth’s ties to fascism and conspiracies to “stir up all the little hatreds of the whole nation against each other” and the use of social/ethnic/racial division to end democracy.

Whatever the merits of the novel, Stewart’s script is topical and shockingly timeless, with lovely turns of phrase and flashes of the sort of wit that decorated the comedies and comic thrillers of the era.

“Did it hurt much?”

“Did it hurt when?”

“Did it hurt much when Hitler kicked you out of Germany?”

Christie has “the Hepburn role” of the flirty reporter who banters with Tracy’s rival writer O’Malley, although a few of the Kate/Spencer exchanges have a nice flash.

The soundstage-bound settings and effects impress in monochrome in ways that a color production would have spoiled. This feels and plays black and white, not “noir” but grimly serious and downbeat.

Even if the story had followed that first act of steady build-up to a fine, furious finale instead of the third act action feeling so shoehorned in, there’s little doubt that Mayer, later a Hollywood Blacklist backer, would have still hated it.

But watching this film over eighty years later, one does wonder if the message of “Keeper of the Flame” was taken as seriously, even back then, as it should be today.

Rating: TV-PG

Cast: Spencer Tracy, Katharine Hepburn, Richard Whorf, Howard Da Silva, Dwayne Hickman and Forrest Tucker.

Credits: Directed by George Cukor, scripted by Donald Ogden Stewart, based on a novel by I.A.R. Wiley. An MGM release on Tubi, other streamers.

Running time: 1:40