Everyone has a “Trump.” No one has a good one.

Like Cher, De Niro, or Walken, there is something distinctive about the way Donald Trump speaks that begs for impersonation, but also, it turns out, something intangible that makes a decent approximation almost impossible.

Trump impressions have become so widespread, we’ve become resigned to mediocrity to the extent that we even gave Alec Baldwin an Emmy Award for his wildly bad take on Saturday Night Live. But sketch comedy is one thing. Broadness is forgivable. What about in the context of real, legitimate acting?

I’ll leave judgment as to whether whatever is going on in Showtime’s The Comey Rule counts as legitimate television to others, but the two-part series, which launches Sunday, features Irish actor Brendan Gleeson in a star turn as Donald Trump, waiting to be scrutinized.

In The Comey Rule, Gleeson’s Trump looms silently in the shadows—a Jaws shark, a Big Bad—more conspicuous and menacing in his absence before becoming a consequential figure in the second half of the series’ action. It’s then that he’s finally unveiled as a comic-book villain, a horror-movie monster, which is more a matter of tone and direction than Gleeson’s performance. Still, his is one of the most naturalistic—and therefore most believable—Trump takes we’ve seen yet.

The series is adapted from James Comey’s 2018 memoir A Higher Loyalty, centering on the period from July 2016, when the former FBI director broke standard protocol and held a press conference explaining the bureau’s recommendation that Hillary Clinton not be prosecuted in its email probe, to his firing in 2017.

It airs in two parts, with Sunday night’s installment examining the circumstances around the infamous 2016 October surprise, in which, less than two weeks before Election Day, it became public that the FBI was reopening its investigation into Clinton’s use of a private email server, only to exonerate her two days before the election—too late, critics say, to undo the damage that that possibly swung the vote in Trump’s favor.

In that episode, Gleeson’s Trump only appears, never speaking. You first see him from behind about an hour in, as he walks on stage during Miss Universe rehearsals in a flashback sequence. He mimes as a FBI dossier is read aloud, narrating the ways in which Russia cultivated him as an asset five years before he was even a presidential candidate.

The second episode, which airs Monday night, focuses on Comey facing the firing squad of an angry public as he navigates a precarious relationship with Trump, who attempts to secure his loyalty, have him squash the Russia investigation, and publicly dismiss the Steele dossier, specifically the notorious “golden showers” allegation.

In a recent interview with The Hollywood Reporter, the series’ writer and director Billy Ray said he convinced Gleeson to take on the role by reassuring him that “our makeup is going to be more real-life than his, our hair is going to be more real-life than his and our suits are going to fit you better than his [fit him].” (Also, interestingly, by agreeing to Gleeson’s request that he not have to do any press around the series.)

It’s a smart move to turn down the volume on the unmistakable visual cues we associate with Trump, at least so much as the Trump aesthetic possibly could be dimmed. You can’t see the blotchy orange skin and not assume you’re watching a sketch character, but there is a more palatable subtlety to the look here. The stringy yellow hair is still heinous and cartoonish, but how do you possibly replicate that look realistically?

One of the reasons it’s so hard for performers to disappear into a Trump impression is because so much of his existence is theatrical, from his look to his manner of speaking to the ego.

There’s been no shortage of takes on Trump in comedy sketches, where the idea is that here is this buffoonish bull of a man charging into a room and taking up all its energy. These are, in essence, pandering performances. If the goal in The Comey Rule is to show a more subdued interpretation of how Trump must exist in the mundanity of daily life, then Gleeson, in large measure, succeeds.

Gleeson’s voice is a little softer than most impersonators try, usually resorting to bellowing every line. If you know that Gleeson is Irish, you convince yourself that you hear hints of his accent come through. But then you realize that some of the weird inflections and pronunciations that Trump employs that don’t conform to standard American English may actually be a little broguish.

In the recreation of Trump’s first meeting with Comey about the Steele dossier, Gleeson makes a meal out of the “golden showers” exchange: “There were no prostitutes. There were never prostitutes. You’d have to be an idiot to believe in something like that.”

There’s something about the way Gleeson says it that seems exactly right, adding the lisp to the last “s” sound in “prostitutes.” There’s a dramatic pause before he says “idiot,” a word that he then breaks into three staccato, separated syllables.

He nails the way that everything Trump says is delivered through a wince. How, when barreling through those run-on, rambling sentences, he breathes in places where people don’t normally take breaths, and never where punctuation would suggest one. How those random sharp inhales are not a gasping for air so much as a pointed hoarding of it, like a vacuum. The forced underbite when he speaks, like he’s purposefully jutting his jaw so that it protrudes forward.

There’s the inherent challenge of how to make anything that Trump says believable, but the saving grace of Gleeson’s performance is his refusal to make it showy. He’s manlier than you might imagine, but that doesn’t negate the whininess—just tempers it a little to keep scenes somewhat grounded in reality.

Perhaps the most indelible thing about a Trump oration is the glaring fact that there is often no roadmap when he starts a sentence, a meandering train of thought that one would imagine would be quite difficult to replicate while reciting lines from a TV script. But it’s in capturing that cognitive, um, “spontaneity” that Gleeson is strongest.

Then there’s what Gleeson as Trump is telegraphing, which is the most important element: that spite and petulance that everyone who has worked with him has described as his modus operandi. Still, Gleeson has to show that the wheels are turning, that there is calculation and thought process there somewhere; it can’t all be brashness.

I wouldn’t say that Gleeson succeeds wholly at making Trump “human.” But that doesn’t seem to be the goal of the series either.

The Comey Rule has had a dramatic road to airing, with the series developed for CBS with the goal of it airing before the election only for executives to get cold feet and instead announce that it wouldn’t premiere until late November, afraid of airing something so politically charged in the lead-up to voting day. (Given the subject matter of Comey’s own “October surprise,” you can’t help but laugh at the irony of this “politically charged” justification.)

Ray wrote and circulated a letter to everyone involved in production, including the cast, explaining his disappointment. It leaked, generating a bit of a media firestorm, and CBSViacom relented and scheduled the series for this Sunday and Monday on Showtime.

That Trump will publicly respond to the series is in some way an inevitability. Whether he will have anything to say about Gleeson’s performance should be interesting; one particularly meta moment of The Comey Rule sees Gleeson as Trump complaining about Alec Baldwin’s SNL impersonation.

Considering how omnipresent Trump takes are on TV, it’s fascinating, at least to me, that the best Trump performance I’ve seen is by a British drag queen named The Vivien in an episode of the RuPaul’s Drag Race: U.K. spinoff. (That’s not shade on The Vivien, either. That’s just how good—and apparently singular—she was.)

Equally so is that we consider lip-syncher extraordinaire Sarah Cooper to be the most adept at capturing the ethos of Trump in an impersonation. That by not attempting the voice or the look at all and instead letting his words and delivery speak for themselves, she exposes his true character better than anyone else.

It’s in that latter element that Gleeson triumphs, attempting an approximation of the person rather than the persona. And he lands at just that: an approximation, though still the closest one yet.