For much of its career, TV on the Radio has been less a band than an idea—and not a very crystallized one at that. According to multi-instrumentalist Dave Sitek, the Brooklyn-based act began as an opportunity for the future Liars and Yeah Yeah Yeahs producer to experiment in the studio. With animator Tunde Adebimpe handling vocals, the duo recorded 2002’s barely distributed OK Calculator, an inclusive-to-a-fault debut. Early appearances in Williamsburg were notable for TV on the Radio’s tendency to surrender instruments to members of its audience. And, as recently as 2003’s Young Liars EP, the duo was still pitching itself as a band that isn’t really a band, one that, to quote Sitek, “[doesn’t] really play live.”

If all of this sounds a bit tentative, that’s because it is. Anyone can hear the promise underlying 2004’s Desperate Youth, Blood Thirsty Babes, the indie favorite that led to TV on the Radio’s major label debut, third and latest full-length Return to Cookie Mountain. On the former album, Adebimpe, unlike most of his postpunk peers, is unafraid to, you know, actually sing, which is why he’s so often compared to pre-punk crooners, such as Curtis Mayfield and, more accurately, Peter Gabriel. Sitek, for his part, dabbles in a lost art as well, alchemically turning indistinct layers of electric muck into backing tracks that suggest nothing so much as a certain ex-Genesis singer’s “Solsbury Hill.” But promise alone doesn’t always cut it. (If it did, reality TV would be much less interesting.) Despite the fact that 76,000 indie snobs—including, judging by his cameo on Cookie Mountain, a fellow New Yorker named David Bowie—clearly feel differently, Desperate Youth seldom sounds better than a glorified demo, a problem in all likelihood attributable to the group’s elastic-band concept. Or, at the very least, its unforgivably chintzy drum machine. Even so, after a single spin of the latest from this newly expanded outfit, only the truest of true believers—or perhaps a significant other or family member—could fail to recognize what a difference a full-fledged rock group makes.

For evidence, look no further than lead single “Wolf Like Me,” a “Sister Ray”–style rocker that finds Sitek, Adebimpe, and post-Liars addition Kyp Malone reinforced by new drummer (in every sense of the word—he’s never been behind a kit before) Jaleel Bunton. Whereas Desperate Youth’s focus track, “Staring at the Sun,” is a wannabe U2 anthem that never quite gets off the ground, “Wolf Like Me” achieves liftoff in mere seconds, as if the core duo had been waiting for years to let rip in front of a flesh-and-blood rhythmist. The quintet, also recently bolstered by bassist Gerard Smith, cuts loose elsewhere, as well, most notably on the speedy, drum ’n’ bass–inflected “Playhouses.” Yet even though a rock band is only as good as its rhythm section, TV on the Radio circa 2006 is distinguished by more than just improved grooves.

To wit, the band no longer sounds like a bedroom project, a development that manifests itself most clearly in hooky Cookie’s headphone-worthy production. That, of course, is the province of Sitek, who finally shows us why Liars and Yeah Yeah Yeahs hired him in the first place. So finely detailed is the tapestry that he weaves on “Hours,” for example, that it takes several spins to pick out guest spots from the likes of Blonde Redhead’s lead singer, Kazu Makino, and an uncredited horn section that is most likely on loan from Antibalas Afrobeat Orchestra.

Just as impressive is the way that Sitek signifies rock without foregrounding the usual suspects. That is, where there are electric guitars, they are either used in brief, samplelike bursts (“I Was a Lover”) or dialed down so low they all but disappear in the mix (“Dirtywhirl”). There are no solos and no lead instruments. Instead, the producer fills the space between beats with retro-futuristic keyboard, louder-than-normal bass, and enough string, woodwind, and percussive oddities to plug a Swordfishtrombone. Noncomformist though it is, none of Sitek’s soundscaping comes close to overshadowing Adebimpe’s vocal contribution.

The difference here is that TV on the Radio’s brain trust either finally realizes, or is finally acting on the fact, that what people want in a rock band is—duh—not the opportunity to be onstage themselves. Adebimpe is, finally, the band’s feature attraction. That much is apparent in the way he’s now mixed, which is often as high as, if not higher than, the accompaniment. My favorite example is the chorus of “Let the Devil In,” a moment that buries the rest of the band under untold layers of booming-from-the-gut vocals. When Adebimpe leads a choir through the refrain—“They let the devil in, he brought his pirate friends/They brought a hunger for blood, and flesh and bone and skin”—the effect is as immense, soulful, and wicked as any power chord that Sitek or Malone might’ve played.

You could also say that Adebimpe sounds just as angry as he did on “Dry Drunk Emperor,” the band’s post-Katrina diatribe against the Bush administration. Released just days after the hurricane made landfall, the Internet-only single offers, among other improbable images, the fantasy of fed-up fathers and sons “marching with their guns drawn on Washington.” The lyrics on the new album, by contrast, are much subtler—and much stronger because of it. For all of Cookie Mountain’s War on Terror–era paranoia, there is perhaps no finer expression of anti-Dubya sentiment than on “Province,” a tune that seems innocuous enough until unpacked in the context of neocon chest-thumping. “Hold your heart courageously/As we walk through this dark place,” Adebimpe and Bowie sing on the chorus. “Stand steadfast erect and see/That love is the province of the brave.”

That this is a more sophisticated rebuke than one would expect from the makers of OK Calculator goes without saying. That it has more in common with the second half of the Good Book than with, say, “All You Need Is Love” just goes to show how serious TV on the Radio has become. None of which would imply that adding a rhythm section or devoting extra attention to production has anything to do with lyrical nuance. But, hey, it can hardly hurt. Right? Besides, the story behind Cookie Mountain is not that this art-rock act is finally, well, rocking. It’s that, for the first time, TV on the Radio the band has caught up with TV on the Radio the idea. It’s good—dare I say, great—and the former at last deserves all the adoration the latter has already received.