When celebrated white British rapper the Streets (AKA Mike Skinner) and his rising-star opening act, white British rapper Lady Sovereign, kick off their North American tour in Seattle, the event probably won't feel much like a mainstream hiphop show—though if history is any guide, you'd think it would. If they were ferrying across the Mersey in 1964 or calling from London in 1977, their audience stateside would have been something like the one that first inspired them: Elvis begat the Beatles begat your mom. But rap is a sound of a different color. This current tour only takes Skinner and Sovereign (born Louise Harman) to midsized venues across the North American white-hipster archipelago from Seattle to Boston, with no dates in Atlanta, Philadelphia, or almost any major hiphop stronghold besides New York and L.A.

"America's never been part of my goals, really," says Skinner, the 27-year-old rapper, producer, and label owner, over the phone from London. "I think because America is so polarized, [hiphop] is not so much about the music, it's about the culture as well. It's not just the beats; it's the voice of black culture. And if you're not the voice of black culture, then you can't be part of that, you know?

"We can't be as polarized as America about that, because we are so much more integrated," he continues. "In England, I kind of speak for all kinds of different people. It doesn't matter how black you are, if you grow up in the UK, then I'm going to mean more to you than any American MC, in terms of actually talking to you, rather than you looking up to [the American MC] for being authentic... And I'm really proud of what I've achieved in the UK, which is to make it cool to be British. Which is not necessarily what I'm responsible for, but certainly my success is responsible for [that]."

He isn't even boasting. Skinner is arguably the most original major new rapper of the decade, on either side of the pond, and Lady Sovereign is a model newcomer in the style that Skinner helped shape—grime. But although Skinner's first two albums created an aural portrait of English working-class youth like hadn't been heard since the Specials, he recently knocked this tidy cultural achievement to pieces with the carefully honed crudities of his third disc, The Hardest Way to Make an Easy Living (Vice/Atlantic). Basically, it just offers a fun, heedless romp through that old pop minefield, success and its discontents.

Numbers about doing too much cocaine frame the album, and in between are sordid tales, like the one about fucking an unnamed celebrity who does crack before appearing on a children's show ("When You Wasn't Famous"), or the one about feeling guilty for not feeling guilty about buying a Ferrari ("Memento Mori"). In general, most of these tales don't register except as jokes that help unseat your expectations, and as a jagged framework that seems to have helped Skinner focus on the real work of the album—his attempt to make the music broader, richer, edgier, and on a couple occasions, more perfectly romantic than ever before.

"Paying attention to form... was a challenge," Skinner admits. "And I'm really proud that I managed to keep it to that."

Lady Sovereign, in contrast, just masters the grime that Skinner has now risen above. Her late-2005 debut EP, Vertically Challenged (Chocolate Industries), is as raw, rude and brittle as anything out of New Orleans or Memphis, but its hyperactive rhythmic counterpoint is a purely British invention, as is Sovereign's manic, West Indian–tinged delivery. That tinge sounds so natural—that is, sounds so black—that it has raised the hackles of some grime fans. But her cheekiness and skill are so basic and winning, it's no wonder she recently garnered a contract with Def Jam simply by proving she could freestyle in a personal meeting with Jay-Z and Usher. Chances are, that touch of cred won't win over many American hiphop headz, though maybe it will give her some distribution. Then, on some distant island, some kid might get a chance to listen, and start scheming.