In the last few years, postapocalyptic dramas have been staggering across the TV landscape like flesh-eating walkers. (This summer, in TNT’s The Last Ship, a virus kills most of humanity; in Syfy’s Dominion, angels did us in.) Consider HBO’s The Leftovers (premieres June 29) a post-postapocalyptic drama–a moody, mournful story not concerned with why the world-shaking event happened but how people carry on afterward.

By the standards of fictional global disasters, The Leftovers’ is a teensy one, just a smidgen of apocalypse. Two percent of the world’s population is gone–not dead, but vanished one Oct. 14 in what is being called the Sudden Departure. It sounds like the Christian Rapture, but it’s utterly random. It takes babies and adults; Christians, Buddhists and atheists; the devout and the drug dealer; plus Gary Busey and the entire former cast of Perfect Strangers. All told, 140 million people are gone, enough that some families are unscathed but no one is untouched. It’s enough to leave the species intact but heartsick; to leave society functioning but rudderless; to leave humanity standing but to kick the legs from under every existing belief system.

The pilot opens with a brief glimpse of “10/14”–driverless cars crashing, children screaming for vanished parents and a mother for her baby. But we see no one disappearing, we don’t hear what it looked like, we don’t even know if the vanishings were witnessed by anyone or caught on security camera, as if to underline that how this happened and why are not the point. Instead, we pick up three years later, as the New York suburb of Mapleton gets ready to mark the anniversary with “Heroes’ Day,” a civic holiday meant to commemorate… well, what? (As the mayor puts it, “No one’s going to come to a parade on We Don’t Know What the Fuck Happened Day.”) “The Departed” is a fitting term for the missing–they didn’t die, they weren’t martyred, they just caught the bus and took God with them.

With no enemy to battle or cosmic endgame to anticipate, the world–at least the little corner we see–has slumped into nihilism. Teenagers play a smartphone version of spin-the-bottle with choices like “Fuck,” “Burn”–you get branded with a hot fork–or “Choke.” The local church is near-empty, but a charismatic British guru named Holy Wayne (Paterson Joseph) is doing gangbuster business offering “healing hugs,” while the disillusioned (among them Amy Brenneman and Liv Tyler) are flocking to the Guilty Remnant, a cult whose acolytes wear white, take a vow of silence and chain-smoke cigarettes. At the center of the story, police chief Kevin Garvey (Justin Theroux) is trying to hold together his family and his marbles, though his more immediate concern is fending off a Heroes’ Day riot between the Remnant and the townspeople who are sick of their memento mori theater. Everyone mourns, no one gets closure. When Kevin tells the wife of a Departed husband, “Sorry for your loss,” she answers, “Is that what it is?”

We’ve seen a lot of moody, ambitious TV dramas–The Killing, Six Feet Under–but none where the mood was so much the whole point. The Leftovers is based on a 2011 novel by Tom Perrotta (Election, Little Children), who co-writes and -produces with Damon Lindelof, the co-creator of Lost, a credit that will probably lead a lot of people to expect The Leftovers to be a much different, more plot-driven series. Here, there are no hatches, no Hanso Foundation, no teasing hints of a conspiracy or a big explanation to come. (OK, the Remnant, with their eccentricities and white uniforms, have a touch of The Others about them.)

The series The Leftovers resembles more than anything is The Returned (Les Revenants), last year’s atmospheric French drama about a small town roiled when dead loved ones come back home, intact. That series was driven by a mystery–indeed, it adapted Lost’s structure of individual character flashbacks–but it was more dream than horror show, examining how people adjust to learning that the end isn’t the end. The Leftovers is like The Returned, but backwards, with Mapletonians cobbling together new belief systems for a changed world (or giving up altogether), but without the zombies and mythology.

And there’s going to be the challenge of The Leftovers in finding an audience. (“It’s like a French arthouse series, but sadder and with less crowd-pleasing genre stuff!” –TIME Magazine.) This show is, and I do not mean this as an insult, probably the least overtly commercial drama HBO has made since the post-Sopranos days of John from Cincinnati, whose big hook was also What It All Means. (Even Luck had horse racing and Treme had jazz.) After Lindelof was criticized for larding up Lost with enigmas and twists, it may be completely unfair to wish that there were more plot and mystery driving The Leftovers. But some viewers will probably have that reaction, and understandably so.

The first two episodes feel unsettled, aimless and seasick–Peter Berg’s trademark jumpy-cam direction contributes to that–jumping around its ensemble to paint a vast mural of sadness. (The opening titles do too, depicting modern suburban characters in a Renaissance religious fresco.) There are striking moments: a flock of balloon doves being released in tribute, Kevin coming upon a pack of pet dogs gone feral (a possible sign of where human society is heading). The show’s melancholy is gorgeous, and Theroux’s Kevin has a kind of exasperated honor, like FNL’s Coach Taylor after a few rough years. But it all seems a bit logy and unreal, as if, like the Remnant with their white garb and silence, The Leftovers made its suffering too generic and surrendered its voice.

Then comes the fantastic third episode, which follows Mapleton pastor Matt Jamison (Christopher Eccleston) through a crisis of faith, all through a story as neatly and twistily crafted as a Twilight Zone episode. The fifth (episode four was not ready at press time) pulls back a bit to go inside the Remnant—led by a quietly riveting Ann Dowd—and examine the reverberations of a brutal crime through Mapleton. And suddenly The Leftovers’ blur distills into focus. The show does have a distinct voice, once you learn to hear it, at once ethereal and hyperrealistic, a combination echoed in the show’s visual language, in which even hallucination sequences are shot in harsh handheld video. It’s one of the truest TV evocations I can recall of the waking-dream feel of actual mourning.

Hey, did I mention that this show is gloomy as all hell? It is, even with a few Lindelofian touches like his taste for ironically jaunty music cues. (“What a Fool Believes” is the “Make Your Own Kind of Music” of episode 5.) Even the best version of The Leftovers, if it proves a complete creative success, will not be a show for everyone. Yet it believes fervently, messily, heartbreakingly, that even two percent of everyone means more than you can imagine.

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