So much theater—old, new, traditional, experimental—is a chore to sit through.

Not Rent. Rent is out-and-out exhilarating, an unabashedly sentimental, sweetly cynical, defiantly exuberant anthem to our age and its antibody heartbreaks, a terribly bittersweet valentine to ageless, eternal heartache-makers like starving artists and star-crossed love. Rent is imperfect, yes, but it’s also what the hype says it is: a milestone, a wonder, a step forward for the modern musical theater.

Jonathan Larson’s landmark rock opera—an AIDS-era, East Village update of Puccini’s La Bohème, if you’ve somehow escaped that information since its off-Broadway debut in January 1996—mines a double handful of pop (and other-than-pop) idioms and almost always produces gold. From the full-throated power-pop balladry of “One Song Glory” and the throat-catching gospel hymnody of “Seasons of Love” to the cheeky, sexy, soulful swing of “Light My Candle” and the snarky musical humor of “Tango: Maureen,” it’s one infectious number after another (has the smooth R&B of “I’ll Cover You” hit the Top 40 yet?).

But Larson’s compositional panache merely makes his show good; what makes it great is that his tunes work beautifully in the context of what is in many ways a traditional book musical. In that, Larson succeeds admirably where heavy rock-musical hitters like Pete Townshend and Andrew Lloyd Webber have largely failed: not simply in writing accomplished pop-rock, but in grafting rock’s vernacular onto the structure a musical has got to have if it’s going to succeed. Townshend, obviously, can write rock, but does that “See me/Feel me” business really move the story? And though Lloyd Webber’s an accomplished theatrical hand, he couldn’t write a legit rock standard to save his wine cellar. (Though I do seem to vaguely recall—with a shudder—that Helen Reddy had a hit ages ago with “I Don’t Know How to Love Him.” Go figure.)

But take “One Song Glory,” delivered early in Rent’s first act by Roger, the handsome HIV-positive rocker and recovering junkie who stands in for Bohème’s Rodolfo: It’s a polished version of that old thing, the I’m-the-hero-and-this-is-my-dream number. And take “Light My Candle,” a duet for Roger and his heroin-addict neighbor, Mimi, that follows hard on “Glory’s” heels: It’s a courtship encapsulated, even if it leaves an essential question hanging to be picked up later in the show. For all their verse-chorus savvy, their catchy hooks and supple melodies, Larson’s songs owe as much to Sondheim and Rodgers and Hammerstein as to the Police and the whilom Prince. Each advances the story; each helps develop a character. That’s what makes Rent remarkable. Until someone (Paul Simon, with his Capeman?) comes along to raise the bar again, Larson has set the rock-musical standard.

Opera newbies won’t miss anything crucial, but Puccini fans will get the occasional chuckle: The opera’s Colline pawns his coat in the fourth act to pay for a doctor for the tubercular Mimi, while Rent’s Collins is robbed of his coat in the first act and robs an ATM in the second to pay for a party that’s disrupted when Mimi shows up near death. In Bohème, lovers meet when the demure seamstress Mimi drops her key outside Rodolfo’s door; in Rent, the druggie stripper Mimi drops her stash—and, while crawling around looking for it, asks Roger if he likes her ass. (Can’t see Mirella Freni doing that, can you?)

Too much, probably, has been said already about the tragedy of the 35-year-old Larson’s sudden death on the eve of Rent’s preview opening. But it is indisputably eerie the way his death—of an aortic aneurysm on the kitchen floor of his seedy New York apartment—echoed the hyperromantic drama his characters live out onstage in his version of Alphabet City. “Forget regret,” they tell each other, “or life is yours to miss”; he died just as his seven-year dream became a reality brighter than he could have imagined. They face “dying in America/at the end of the millennium”; he got there ahead of them, and his work became his elegy.

At the National Theatre, his mourners—in a bare-brick graveyard dominated by a Rauschenbergesque scaffolding of bike tires, auto parts, street signs, and shopping carts—are Mark Cohen (Luther Creek, a little rabbity and a lot endearing), a vaguely geeky filmmaker whose parents check in regularly from Scarsdale via voice mail; Roger Davis (Manley Pope), the embittered rocker who shares his frigid loft (and hasn’t left it much since his girlfriend left him a suicide note that explained, “We have AIDS”); their old roommate, the digital-age philosophy professor Tom Collins (C.C. Brown, a confident and winning presence), and his new boyfriend, a drag diva named Angel Dumott Schunard (an utterly fabulous Stephan Alexander, who really makes that shower-curtain skirt work). Standing with them are Mark’s ex-girlfriend Maureen Johnson (sparky Amy Spanger), a flaky conceptual performance artist, and her new girlfriend, lawyer Joanne Jefferson (Sylvia MacCalla). Between the title tune and the wrenching face-the-footlights finale, they survive muggings, evictions, support-group meetings, a Maureen performance in which the audience is asked to moo at the moon with her, and a showstopping production number that has the entire 15-member cast dancing on a pair of long steel tables in defiant celebration of “La Vie Bohème.”

And death; always, there is that specter just around the corner. Of the seven principals, four carry the AIDS virus. Only one dies—but then in circles like theirs, like ours, even one death is like a landslide, providing as it often does a horrifying preview of what may come all too soon for those of us who stand at the bedside.

Admittedly, there are mawkish moments; the occasional lyric veers to the wrong side of doggerel, and the second act sometimes seems less like a structured narrative than a holding pattern; breakups and makeups occur and recur with little obvious reason. But these are things that Larson might have been able to fix if he’d had the chance; none of them really undoes the piece.

One or two of the 30-odd numbers (Maureen and Joanne’s “Take Me or Leave Me,” for instance) don’t seem to have quite the electricity at the National that I’ve heard in them elsewhere, but by and large the tour cast is smashing, a tight, insanely energetic ensemble. Most remarkable, perhaps, is Simone (the mononymic daughter of Nina Simone), who plays the HIV-positive junkie Mimi; she’s a stunner, as richly sweet as honey and as dangerously seductive as the heroin she craves.

At the end of the driving first song, Roger and Mark lament that in their world—looking up from a place that’s not at the bottom of the social ladder but from which the bottom can be clearly seen—the rules don’t always seem to apply. “Everything is rent,” they cry, establishing the double meaning of the show’s title; the social fabric has been torn asunder, and there’s some question as to whether it can be stitched back together.

Rent doesn’t suddenly make it possible; that’s not the role of art. But it inspires hope—which is.CP