Rumors of their demise have (once again) proved premature: André 3000 and Big Boi of OutKast.

The Odd Couple

Recall for a moment your best friend in high school. If yours was like most such friendships, one measure of your intimacy was a willingness to talk unguardedly about your most immodest plans for the future: the band you would form, the business you would start, the moguls you would become, the envy you would inspire, the women you would awe, the cars and houses and toys of every description you would buy, the bond between you so strong that none of these changes would weaken it.

Now imagine that every single one of those plans came true.

That is in effect the story of André Benjamin and Antwan Patton, better known as André 3000 and Big Boi, best known collectively as OutKast, the biggest-selling and most critically adored hip-hop act of the last decade. They met at age 15 and yoked together their dreams of one day becoming famous rappers, and everything they saw in their most sustained flights of 10th-grade fantasy is now their real life: their last album sold 11 million copies, won three Grammy Awards and topped several critics’ year’s-best lists, and they are the stars of a new movie, “Idlewild,” which opens later this month. All that success makes for a strange sort of friendship — one that is built on love, trust and a kind of shared amazement that no one else could understand but also on a fidelity to a fixed idea about themselves, a fidelity that has grown increasingly awkward, because even a man whose every dream has come true is not necessarily the same man at 30 that he was at 15.

What they have together, in fact, is as much like a marriage as a friendship, in which each man’s tendencies harden the role in which his partner finds himself cast, and in which there’s a lot of talk about moving on but never any actual moving on. What’s compelling about OutKast isn’t simply that the interests of two old high-school buddies should have diverged; it’s that Big Boi and André have somehow contrived to turn this incompatibility to their musical advantage. The same forces that have destroyed innumerable bands and other creative partnerships — marriages, for that matter — have somehow made theirs more successful, so that the less Big Boi and André interact at all, the better OutKast’s music gets as a result. They are like a high-functioning Lennon and McCartney of hip-hop, capable of rock-star behavior around strangers but remarkably egoless around each other. It’s hard to think they can keep up this strange collaboration for much longer; but people have been saying and writing that about them for almost 10 years now, and the increasingly theoretical entity called OutKast just keeps getting stronger.