Liam Neeson plays the real-life "Deep Throat" in Peter Landesman's portrait of leaker Mark Felt.

The first thing to say about Peter Landesman's Mark Felt: The Man Who Brought Down the White House is that it is not the B-side to All the President's Men, the movie that immortalized Felt (albeit anonymously, as Deep Throat) for the moviegoing public. It doesn't cast that picture's procedural spell, or dovetail with its narrative on more than a couple of occasions. The second is that it has little if anything to say to our own moment, in which a sizable percentage of Americans (to say nothing of the world's other inhabitants) are rooting for our own Mark Felts, whatever their motives may be, to expose executive malfeasance.

Instead, what the picture is about is right there in its title — offering insight into one of history's great whistleblowers, one whose power to intrigue grew during the decades his identity remained secret. It's a role very well suited to Liam Neeson, whose righteousness fills the screen and sometimes seems all the movie can offer. The solid ticking-clock biopic should perform respectably among serious-minded moviegoers, but lacks the oomph of a must-see.

Mark Felt is a 30-year veteran of the FBI when we meet him, during the final year of Richard Nixon's first Presidential term. (Onscreen titles keep reminding us how many days remain until the election.) Long a trusted colleague of J. Edgar Hoover, he enters the film just as he's being asked, more or less, to betray him: A few of Nixon's officials have brought him in for a meeting, asking the smartest way to fire Hoover. Felt replies with something of a diplomatic non-statement, then continues with a reassurance that sounds very much like a threat: He informs his questioners that every bit of gossip entering FBI offices — when an official is "seen with a woman not his wife...seen with a man, not his wife" — is written up in a memo, and all the memos go through Felt on their way to J. Edgar's files. "All your secrets are safe with us," he insists — perhaps the classiest way he could possibly paraphrase the sentiment "Nice Administration y'got here, fellas. Shame if somethin' should happen to it."

According to Landesman's screenplay (based on books by Felt and John D. O'Connor), Felt wasn't a bully or manipulator but a true believer. When he claims that the Bureau is "the most respected institution in the world," he seems to mean it; and the surest way to puncture that institution's integrity, according to Felt, is to let any other government body exert control over it.

Which is just what happens when Hoover dies and, instead of promoting Felt to the directorship he deserves, Nixon appoints L. Patrick Gray, a man with no law-enforcement experience. Felt is sure he's too loyal to Nixon to do his job independently; and if the rest of us need convincing, we get to see Gray at his desk in a turquoise polo shirt while all his underlings wear sober G-man suits.

Gray acquiesces to pressure regarding the new investigation into the Watergate break-in, telling Felt he has 48 hours to wrap things up. Felt is indignant, and of course keeps digging. The movie never explains how this deadline is overcome, but it watches raptly as Felt commands loyal investigators over the coming weeks, furious that "the goddamn punks are running the country."

Though Neeson is surrounded in this office by some fine actors (including Brian d'Arcy James, a reminder of how much better Spotlight was at turning investigative work into captivating cinema), the movie makes too little effort to establish them as characters. Josh Lucas' Charlie Bates gets the most attention, with strong hints that he knows Felt is the source of the leaks causing increasing office friction. But this is not an ensemble picture.

About those leaks: Here, Felt's illicit communications with Bob Woodward are less compelling than his sit-downs with Sandy Smith (Bruce Greenwood), a Time magazine reporter also covering the Watergate scandal. Despite the script's lack of subtlety (it needs to tell us multiple times that, prior to this, the straight-arrow Felt had never given Smith a single secret in their long acquaintance), the chemistry between the two actors as they meet in a dim diner represents some of the film's most effective drama.

Needing to broaden his portrait beyond Watergate (and to erect a thin defense against accusations of hagiography), Landesman sometimes awkwardly weaves in references to the lawman's non-whistleblowing work. Most important is the acknowledgement of his efforts to take down the Weather Underground, militant activists both he and the White House feared. Several years after his retirement, Felt was convicted of violating the Constitution in his pursuit of the activists. (Ronald Reagan pardoned him.) But the scene here in which he orders that crackdown — which others object to as a return to Hoover's "bad old days" — feels tacked-on, less an obligation to history than a way of solidifying a subplot in which Felt worries that his daughter Joan, who disappeared many months ago, might have joined the militant left.

Historians will likely have much to say about this picture, which, despite its acknowledgment that personal grievance had much to do with Felt's whistleblowing, still paints him as basically noble. But as in his Concussion, Landesman seemingly is too enamored of those who go up against the powerful to let us decide on our own how their righteousness balances out against their faults.

Production companies: Mandalay Entertainment Group, Torridon Films, MadRiver Pictures, Endurance Media, Scott Free Productions, Cara Films, Riverstone Pictures

Distributor: Sony Pictures Classics
Cast: Liam Neeson, Diane Lane, Marton Csokas, Ike Barinholtz, Tony Goldwyn, Bruce Greenwood, Michael C. Hall, Brian d’Arcy James, Josh Lucas, Eddie Marsan, Wendi McLendon-Covey, Maika Munroe, Tom Sizemore, Kate Walsh, Noah Wyle, Julian Morris
Director-Screenwriter: Peter Landesman
Producers: Ridley Scott, Giannina Scott, Marc Butan, Anthony Katagas, Peter Landesman, Steve Richards, Jay Roach
Executive producers: Yale Badik, Des Carey, Colin Wilson, Peter Guber, Jeffrey Vinik, Nik Bower, Deepak Nayar, Michael Schaefer
Director of photography: Adam Kimmel
Production designer: David Crank
Costume designer: Lorraine Calvert
Editor: Tariq Anwar
Composer: Daniel Pemberton
Casting directors: Lindsay Graham, Mary Vernieu
Venue: Toronto International Film Festival (Special Presentations)
PG-13, 102 minutes