When dancehall icon Capleton plays The Pinnacle tomorrow evening, he will be doing so as an artifact from a bygone era. Just last year, the modern strain of Jamaican dancehall was tapped as the heir apparent for clubgoers and music buyers looking for something to offset their long jags of hip-hop chart toppers.

All of this came to a grinding and justified halt when some curious journalist decided to Google the dancehall colloquialism "batty boy" and turned up some troubling search results. With lyrics like "Boom bye bye/ inna batty boy head" and a police dossier implicating Buju Banton in a violent assault on a gay man in Kingston, the new movement proved impossible to seriously champion. The ignominy created considerable and wholly appropriate worry points even amongst those of us comfortable with separating the occasionally repugnant opinions of people like R. Kelly and Mike Jones from the thrilling music they use to convey them.

We didn't have to worry for long. Just weeks after the story broke, concerts were picketed, tours were pulled and even innocuous club-fillers like Beenie Man's exhilarating "Dude" vanished from radio. Into an era accustomed to both vigorous social progressiveness and the gentle lampooning of the same, dancehall had thrust the classic Leni Riefenstahl scenario: How do you appreciate the considerable artistic merits of a performer while being consistently confronted with his or her repulsive and bigoted social agenda? It's a struggle blue-state fans of contemporary country must have to endure daily.

Capleton's successor, and the dreadlocked embodiment of reggae's hopeful do-over, Damian "Jr. Gong" Marley, released his debut record last Tuesday to near-unanimous acclaim. No great surprise — there's a lot working in this man's favor: His record, Welcome to Jamrock (Universal), is easily one of the year's best, a riveting and exuberant hybrid of classic limber roots sound and a steely hip-hop aesthetic. It boasts a respectable cache of guest appearances: everyone from The Roots' Black Thought to reggae legend Bunny Wailer. What's more, though, he's got an incontestable last name. The whiskey-throated progeny of the reggae lion college fraternities have spent the last 20 years ruining, Jr. Gong represents a shift in the reggae methodology and a return to the rubbery riddims and strict Rastafarianism that characterized its earliest stars.

What's fascinating about Jamrock, besides its easy, instant singability, is the way it cleanly retools the dancehall formula and sinks a classic sound into the modern era more gently. Dancehall songs hit with a furious punk! punk! punk!, but Marley takes it slow, working a lissome groove that wins over time. The closest sonic references are the singles Sly & Robbie produced for their Taxi label in the mid-'80s, one of which, Ini Kamoze's "World A Reggae," Marley bit whole for the album's first single. Songs like the jubilant "We're Gonna Make It" and "Khaki Suit" have a loose, easy cadence, juxtaposing light, bobbing basslines with brisk organ stabs. Where dancehall's more reprehensible offerings bristled with violent excoriation (Capleton once claimed the "fire" he wanted to burn homosexuals with was a "righteous, cleansing fire"), Jamrock instead abounds with exhortations to strength and moral purity. As in the great entries introduced into the genre by the senior Marley, as well as those by Max Romeo and Linval Thompson, the world is derided as Babylon, a moral black hole teeming with traitors, liars and swindlers. Politically, it isn't much better: Government bureaucracy (what Peter Tosh used to refer to disgustedly as "the shitstem") exists purely to grind down the poor and powerless and "gamble the youth dem life like racehorse."

In what is perhaps its most striking contrast with dancehall, Jamrock is aggressively monogamous. Where Beenie Man begged impish permission to "ram it and stick it and jam it," Marley's lady, in one of the record's best lines, praises him for thinking with his "mind and not [his] peanuts." In the melancholy "Pimpa's Paradise" he laments the fate of a young woman who wrecks herself with a steady diet of hard drugs and crass men. It may be the first song in 15 years in which the word "pimp" doesn't sound like something to aspire to.

The record is already netting considerable success. Its title track has attained a ubiquity Capleton and Sizzla only dreamed of, and it managed to sell 84,000 copies in its first week, debuting at a respectable No. 7 on the SoundScape chart (just behind the new record from Paul McCartney). And aside from a throwaway conflation of abortion and murder that's probably not going to win him any fans at NARAL, Marley has kept his album free of strict pronouncements on social issues. In the end, Jamrock succeeds because Marley focuses not on the jot and tiddle of the law, but on the spirit of the thing: to encourage those who are suffering under the grim, enduring rule of a wicked, clueless, corrupt government. Marley sums it up effortlessly near the end of "Welcome to Jamrock," his stern, resonant voice attaining the holy conviction and mystical authority of a cantor: "Welcome to Jamdown, poor people dead at random/ Political violence, bare ghost and phantom … to see the sufferation sick me/ to win elections, dem trick we."

Sound like any place you know?

Capleton plays Fri., Sept. 30, 9 p.m., $25, with David House Band, Pinnacle Nightclub, 720 Arch St., 215-413-7720.