Big Boi and André 3000 may be hip-hop's oddest couple, but as OutKast they've fused their disparate personalities into one of the genre's most durable duos. Jim Carroll meets them in the UK, where they're preparing the way for a new album and film before taking a spin on the London Eye - and sampling some absinthe

ABSINTHE is making OutKast's hearts grow fonder. "Yo, what's the story with this absinthe stuff, man?," Big Boi asks. "Will it blow my mind if I drink it?"

Outkast's Big Boi and André 3000 have heard loads about the Green Fairy and they're intrigued. They intended to try a few glasses some nights previously in Paris, but now they're in London and they've decided that today is going to be their absinthe day. "Is it like glowing green?" wonders André. "Like radioactive shit?"

OutKast are in London to let people know that they have a new album and film (both called Idlewild) on the way. Accordingly, the day will be spent in a hotel suite doing interviews. In the evening, Big Boi, André 3000 and a few hundred guests will go round and round on the London Eye. As the 32 pods turn on the largest Ferris wheel in the world, the plan is that the new album will be the soundtrack for the trip.

In one of these pods, over four hundred feet above the Thames and the Houses of Parliament, two of hip-hop's most valuable players plan to be on a very different kind of trip as they toast the English capital with absinthe.

No matter how much they protest to the contrary, the pair remain hip-hop's oddest couple. In the right-hand chair sits André "3000" Benjamin, a softly-spoken man with a floppy hat who wants to talk about art, cartoons and fashion. In the left-hand chair slouches Antwan "Big Boi" Patton, a smiling hip-hop player who will talk enthusiastically about his love for pitbulls and Kate Bush. Now and then, Big Boi shouts "time for another sexy party" in a faux-German accent and both OutKasters collapse with laughter. I guess you had to be there.

"OutKast is about personal expression and individualism," says André grandly and Big Boi nods his head furiously in agreement. "I can't force Big Boi to be something he's not and he can't change me. That's the beauty of OutKast. God put us here to play certain roles.

"There may have been times when I was a little timid and Big Boi would just tell me 'do that shit. You ain't got no pants on? Shit, go out there in your underpants, boy'. I might bring a tune to the table which has a whole bunch of crickets beatboxing, and Boi's the one who then points me in the right direction."

It's a partnership that goes right back to the old-school: Tri-Cities High School in East Point, Atlanta, where the pair met in the late 1980s.

"From 10th grade, it's always been tight between us," says Big Boi. "We started out talking about music and girls and shit and just went on from there. Of course, as with any relationship, we've had our ups and downs. We've never had a personal falling out. It's always been business decisions which make you go what the hell is going on here?"

There have been many good and bad "what the hell?" moments from OutKast. When the cosmic funk of their breakthrough Stankonia album sent them soaring to the moon in 2000, there was a sense that their time had come. It appeared that nothing could stand in the way of the act that had put southern hip-hop style on the international pop map.

Yet all that came in Stankonia's wake were rumours of trouble, splits and tantrums. 2003's double-CD Speakerboxxx/The Love Below added more fuel, each MC taking a walk on the solo side and watching as Hey Ya became a big ol' smash hit. Big Boi was happy to tour, but André wanted to paint, act and dream. The end, it seemed, was nigh.

Of course, nothing of the sort transpired. Today, both are happy to sit side by side and fly the OutKast flag. All is sweetness and light. Jokes are cracked. Hands are clapped. There's nothing wrong here which couldn't be cured by a few spoonfuls of absinthe.

"People hear these stories about me not wanting to tour and other fake-ass shit, but they don't hear what's really going down," insists André. "The touring thing? That's true, that's a personal decision I took. I just lost any excitement or passion I had for doing it. I'm trying to set up the next five to 10 years of my life so, by not touring, I have the time to do other things that I want to do at the age of 40.

"I talked to Big Boi about it a long time ago and he's happy with it. He's still out there, being a wild boy and doing his thing, but it hasn't changed the fact that we're still close, we're still homeboys."

This brings a string of "hell, yeahs" from Big Boi. After all, the Boi points out, there's a new album on the way and that worked out mighty fine.

"Of course we do things separately, but it's a good kind of separation, like an incubation period. The biggest thing that's changed is that we're not in the same place at the same time. But we both learned how to write, produce and do the melodic funk thing together so we can trust each other to come correct. It's like having two separate cubicles in the same company and meeting in the boardroom to get things right."

What's emerged from the OutKast boardroom this time out is Idlewild. Their sixth album is also a soundtrack-that's-not-quite-a-soundtrack ("the record company wanted a straight-up OutKast album, but it's both") for OutKast house video director Bryan Barber's musical of the same name.

The flick features Big Boi and André 3000 dodging bullets, booze and broads in a world of speakeasy jazz dives and sharp suits. To get in the mood, the pair listened to a couple of Cab Calloway tapes and watched Stormy Nights and Casablanca. "It's our take on the '30s, a hip-hop '30s," says Big Boi.

Idlewild is their third movie project and the first to go all the way to the big screen. "We've got the clout now, baby," Big Boi hollers. "We've sold millions of records, so naturally people will take our calls because they want to buy into the OutKast brand and what we're all about."

But, for all that, Big Boi acknowledges that Idlewild was still a risky proposition for Universal Pictures.

"For one, it's a period piece and they don't play well in theatres. A black period piece? Man, people definitely don't go to see black period pieces, not even black people. A musical? People don't go see musicals. First-time actors? First-time director? Hell, I'm not putting any of my money into this! It was by the grace of God that this got made."

Of course, making movies and multimillion selling albums was just a dream when OutKast first started out learning their trade back in Atlanta. "All we wanted to do then was rhyme and rap," recalls Big Boi. "We didn't have no money, no cheese. Back then, all you had was a big stack of records, your thoughts and a notebook.

"You'd have some change to go down to the store to get some juice and a turkey sandwich. But you got a certain kind of music out of that situation and our early records reflect that. These days, we ain't having to hustle so we write about different things."

But hip-hop, notes André, has also changed since then. "When we first started listening to hip-hop, even before we laid down tunes, it was just music, this one little thing. Now, you got ring-tones, downloads, hip-hop tunes on commercials. It's become the new pop music. It outsells rock, it outsells country."

Even the sound of the south is tolerated. "When we first came up, to mention the south in hip-hop was a no-no," says Big Boi. "We started out listening to people like Scarface, 8Ball and MJG, Poison Clan and Raheem The Dream. Those sounds from back then are pretty much the same thing as what they're doing now. Of course, it has been updated a little and there are new cats and slang and rhymes, but when you go New York or LA, 75 per cent of the hip-hop you hear on the radio are southern bangers."

What André wants to hear now is the next great leap forward. "We're kind of at a transitional point where you wonder what's next. It's happened with every other form of music, so hip-hop will be the same. The people who are making it will have to look at new ways of doing it to keep it going, to keep it fresh."

OutKast's own approach to making beats remains the same. "You hear a sound in your head," says Big Boi, "and you go 'damn, how do I make that whooomph sound with what I have in the studio?' You go looking for a tuba or a German oompah band or something. You never know where a song will end up. You get an idea and you run away with it. We didn't set out to make a big pop hit with Hey Ya. Hell. We probably couldn't do that if we tried."

Away from the studio, both juggle a slew of non-OutKast bits and pieces. André has a new animated TV series, Class of 3000, coming on the Cartoon Network and there's his fashion brand ("its about feeling good when you look in the mirror before you leave the house").

And Big Boi? Well, he just goes to the dogs. For $900, you, too, could acquire a pitbull puppy from his Pitfall Kennels outside Atlanta. "I've about 80 to 100 on the farm now. I've got my brother running things because I have to go to Europe and drink absinthe and talk to Irish guys. We're booming. We just sold some dogs to 50 Cent."

The pitbull business has also set Big Boi thinking about other four-legged enterprises.

"I've thought about greyhounds. Oh yeah, I even went to the dog track. They're lean as fuck, aren't they? I thought about getting into the horse business. For real, some real Seabiscuit shit. I found this fine-ass horse, all-black with an all-white mane. I want to put that horse on the track, I want to run him in the Kentucky Derby. It's fly to have a horse and all that, but they win serious money too. And then there's the stud fees afterwards."

Hip-hop's would-be John Magnier leans back in his chair and laughs loudly. "You never know what's in the barrel, man, you just never know."

An OutKast truism if ever there was one.

 Idlewild the movie is released on October 8th