The show follows the misadventures of a double agent loyal to the Viet Cong referred to only as “the Captain” (Hoa Xuande) as he struggles to keep the North Vietnamese, the South Vietnamese and the CIA happy while working as an operative in the United States. His mission had originally been to infiltrate the South Vietnamese and acquire intelligence he could feed the North. This he did so successfully that he became aide-de-camp to the general in charge of the South Vietnamese secret police (Toan Le). He even took up residence in the general’s home while also deceiving an American operative named Claude (Robert Downey Jr.) who recruited him as an asset at a young age and trained him in CIA interrogation tactics. When Saigon falls and the general flees, the Captain “flees” with him — on orders from his childhood friend Man (Duy Nguyen), his North Vietnamese handler in counterespionage, who wants him to monitor the general’s activities in the United States.

You’ve got to be pretty fluent in multiple ideologies — and persuasive at acting like a true believer — to pull all that off. Alas, the Captain’s ascent in the ranks, and most of his more sophisticated spycraft, happens off-screen. By the time we meet him, he’s broken and oddly incompetent at projecting anything remotely resembling the kind of ideological purity his profession requires. We might chalk this up partly to the Kafkaesque nightmare of being imprisoned by his own side. The story begins there, at the end, in a North Vietnamese reeducation camp. In lieu of the hero’s welcome he expected, the Captain is tossed into a sweltering cell where he is ordered to pen the “confession” that structures the show. “Start at the cinema,” one of his captors says.

The Captain doesn’t. Instead, he writes the following lines: “I am a spy. A sleeper. A spook. A man with two faces. I was cursed to see every issue from both sides. I was a Communist agent implanted in the South.” It is, whether he understands it or not, a small act of rebellion. Not only does this not start at the cinema; it begins with, of all things, him. In lieu of a confession tailored to the party’s ideological framework, he’s producing … memoir.

It’s not the first time. The Captain has (we learn) already squandered a full year failing to produce an account that will prove to his comrades that he has been successfully “reeducated.” Instead of producing the stripped-down, suitably repentant document containing the details his superiors insist he’s suppressing, the Captain can’t help but get fancy. Metatextual. Maudlin. He keeps presenting the revolutionaries with plotty, sentimental drafts so baroque and dramatic that a supervising commandant — whose editorial interventions pepper the series — mocks him at one point for ending his confession on that Occidental barbarism, a “cliffhanger.”

If this sounds two ticks funnier than it should, you already understand something crucial about “The Sympathizer.” Namely, that the tone — for audiences who expect certain things from spy thrillers and American stories about Vietnam — is just a little bit wrong. That a dedicated Communist who loyally served the Viet Cong ends up their prisoner feels right and proper; this is the kind of broad, anti-Communist tragedy Americans expect and produce. That the form the Captain’s punishment takes is a Sisyphean series of meetings with a picky, unsatisfiable editor, however, is hilarious. Thus does this show proceed, with extremely funny predicaments overlaid atop broadly schematic situations we can (and should) recognize as desperately serious, even dire. It just isn’t the mode of violence we were expecting.

Xuande does heroic work anchoring these competing tones and humanizing the slightly schematic nest of contradictions slowly paralyzing his character. The Captain, we are told (perhaps one time too many), is a double agent in more than one sense. Half-Vietnamese and half-French, he was cruelly rejected by the Eastern and Western worlds he must nevertheless master and learn to navigate. After his mother dies, his only real remaining bond is to his two childhood best friends, Bon (Fred Nguyen Khan) and Man. Bon fights for the South. Man fights for the North. The Captain secretly sides with Man and openly sides with Bon. His position is, as ever, torturous and tentative. He’s an ideologue who must cajole and compromise and dissemble. A true believer who can never profess. Stuck between North and South, East and West, friend and friend, he can’t fight. The only weapon available to him is a neutered form of diplomacy.

This is a spy thriller, in other words, where the double agent’s defining characteristics are that he doesn’t fit in and that he is — compared to the spies we get in cinema, anyway — only intermittently competent and more than a little bit bland.

“The Sympathizer” signals from the start that it shares with its protagonist a compulsion to rebel against the genre it’s supposed to deliver. This is, after all, a TV adaptation of a book. And yet it can’t stop talking about — or referencing — film, a genre the novel specifically (and savagely) lampoons. Sure, the series theoretically understands its mission: It obligingly dedicates an episode to a withering parody of “Apocalypse Now” and “Hearts of Darkness,” the documentary about that film’s production, and makes some points about Asian representation. But, like its protagonist (this is a theme!), it can’t help but betray a secret attraction to the stuff it’s supposed to oppose. The show even packages itself as a movie, opening with the comforting whir of a projector and the flickering speckles and dots you might see on ’70s-era film. “Start with the cinema” might be the show’s (and the Captain’s) mantra. Both squeeze in references to “Death Wish” and “Emmanuelle” to set up an interrogation scene taking place in an empty movie theater — which of course permits everyone to comment on the scene’s theatricality.

At its best, the show defies expectations from a peculiar angle, lapsing into anticlimax where we expect shock or catharsis and vice versa. At its least surprising, it declares an explicit intention to reframe: “In America it is called the Vietnam War. In Vietnam it is called the American War,” the opening text reads. It’s a statement of fact, but there’s a whiff of the kind of tit-for-tat mentality Americans would rightly fear. Or, at the very least, a willingness to commit America’s narrative crimes against Vietnam in reverse. And, indeed, the show delivers a hilarious version of exactly that, casting Robert Downey Jr. as precisely the kind of depthless, generic villain Asian actors so often play in American films. His roles include Claude, the CIA agent, a bald Orientalist professor, a condescending Senator hellbent on fighting Communism and a volatile auteur. Making him play all those parts feels like a very good nested joke along precisely those revanchist lines.)

At its best, though, the show surprises the viewer with layered portrayals of people we don’t expect to be portrayed with layers — such as the general, whose crimes are considerable, but whom Le plays as variously baffled and desperate and volatile and depressed. Or Sophia Mori (Sandra Oh), a Japanese American woman who navigates some of the same hybridities the Captain struggles to integrate with comparative serenity. Or the South Vietnamese official the Captain ends up murdering to maintain his cover, whose amiable affect and fits of generosity can make you (and the Captain) forget certain horrifying activities in which he participated. This is of course the pun at the title’s heart: the Communist sympathizer ends up sympathizing too broadly — in a way that humanizes his enemies, prioritizes his friends and distracts from his mission.

Those fiddly shades of gray — the series’ best — necessarily recede as the plot progresses. The last episodes are inferior to the first three (which Park Chan-wook directed). That’s not a condemnation. It was probably inevitable that this show’s extraordinary visual and narrative confidence would falter as it tried to square the ideological schema in which its characters operate with the wonderfully messy story about them it produced.

The Sympathizer premieres April 14 on HBO and will be available for streaming on Max, with subsequent episodes airing weekly.