You might think you know Phoebe Waller-Bridge. You might, like me, even think you love her a bit, a consequence of being seduced, and then bludgeoned remorselessly, by the brilliance of her art.

But you don’t know the half of it.

Waller-Bridge became something of a household name — especially if your household is literate and dysfunctional, with a taste for the ribald and outré — with the 2016 U.S. release of her BBC series Fleabag, an uncompromising situational comedy that is equal parts tragic and comic, queasily mesmerizing and, in the end, fantastically cathartic.

The show, which follows the romantic and sexual exploits of a 30-something British woman who is reeling after the apparent suicide of her business partner in a failing café with a “guinea pig theme,” revamped all ideas of what a sitcom can do. With its in-folding narrative, which routinely breaks the fourth wall with a wicked wink, Fleabag shattered the cozy communal hugger-mugger of Sex and the City, turning its alienated lead character into a quixotic figure tilting at the whirling windmill of her own devastated psyche. 

At the center of it is Waller-Bridge, whose unhinged candor, inverted vulnerability and spindly armor of gallows humor make her the reluctant anti-hero of the post-feminist flail. Men have been playing this psychosexual game of asshole confession for millennia, but to see a woman doing it — raw, unfettered, narcissistic, self-damning — was a revelation. The humor Waller-Bridge squeezes from Fleabag is an act of busted grace, a slapstick valediction at the end of our innocence.

Here’s the thing, though: As great as Fleabag is, the series is but a diluted reconstruction of its source material, which is Waller-Bridge’s one-woman theatrical monologue of the same name. This is hardly an indictment of the television show, which is marvelous; rather, it’s a nod to the shattering emotional power of hearing and watching Waller-Bridge tell the story alone on a darkened stage, left to her own devices and shorn of human adornments. The echo chamber, in this sense, is loud in a way the show never could be. And silent, too.

In a mere 80 minutes, Waller-Bridge builds the story of Fleabag to a crescendo that will knock you flat on your ass. She does so in curlicues and flashbacks that were expertly adapted into the series, but here they are more disarming, creating escape hatches of humor that, thanks to the singular focus on one woman talking, better reveal the singed state of her soul. Familiar characters and subplots — the rodent-mouthed subway lover, her emotionally distant father and high-achieving sister — are present, but they are condensed and channeled through Waller-Bridge herself, to stunning effect.

To tell you where the monologue differs from the resulting series would be to ruin the outcome; just let it be said that the differences are significant, leading me to question how or why the BBC production chose to strip crucial elements from the narrative, especially the final 20 minutes or so. They are as emotionally fraught as anything I’ve seen in a long time.

Then again, the book — or, in this instance, the monologue — is almost always “better than the movie,” as they say, and here the tragic vitality of Waller-Bridge’s writing comes to the fore. It’s not exactly the case that new information is added in her solo performance. Rather, the different tone and tenor of the staged Fleabag reveals an earnestness and existential depth that isn’t fully reflected in the show. It’s on stage, unplugged and stripped bare, that the full magnitude of Waller-Bridge’s artistic genius becomes evident.

She is, in my estimation, one of the finest poets of despair currently at work, and the humor she plies in unearthing the sources of our current malaise — disconnected, oversexed, grasping for meaning in a modern wasteland — strikes a dim spark of hope amid the clamor and chaos of most consumer entertainment. Waller-Bridge is the real thing: a serious artist pushing hard against the boundaries of what can be said and shown, and doing it in such a way that we can laugh as we’re taken apart by her vision.

A special live recording of Fleabag at the London’s National Theater will play 1:30 pm Saturday, Feb. 22, 7:15 pm Monday, Feb. 24 and 7:15 pm Wednesday, Feb. 26, as part of Broadway Metro’s MetroArts Stage series; premium prices of $16-$19 apply, tickets as BroadwayMetro.com.