The New Kids in the Flat : THE FOURTH GENERATION OF ‘REAL WORLD’ ROOMIES SHARE THEIR LIVES IN A LONDON FISH BOWL. CIVILIZED BEHAVIOR? HARDLY.

Seven young people lounge around the dinner table discussing the subjects nearest the forefront of their minds--body parts, body fluids and body hair. Or are they just showing off? In a nearby “control room,” adults gathered around monitors peer into MTV’s “The Real World,” and they’ve heard enough.

The director decides to change the topic to something more edifying. He dispatches a note via the cameraman to the nearest cast member; it lists the itinerary of the cast’s upcoming all-expenses-paid trip to Kenya. Notable on this schedule is the daily 5 a.m. wake-up call. When he hears about this, Lars, a party guy from Germany, gripes, “That means we’ll never sleep.”

This is typical interaction at 18 Powis Terrace, a few blocks from the Portobello Road antique market, where 12 MTV cameras are watching these carefully chosen youths interact, like boys and girls in a plastic bubble, in the fourth edition of the popular docu-soap, which bowed last week.

Since “The Real World” debuted in May, 1992, it has been “consistently one of the top-rated shows on the channel,” says Lisa Berger, MTV vice president of talent and series development. “When it first started, we had no sense of how popular it would be. But the peer nature of the project makes it unique.

“These people are so real. Viewers identify with them and see how they live their lives. Our core demographic is 18 to 24, but I always like to say 13 to 35 because 13-year-olds want to be 18, and 35-year-olds want to be 24.”

The first “Real World” series, set in New York City, lasted for just 13 episodes. The following seasons in Los Angeles and San Francisco were increased to 22 because viewers wanted to spend more tightly edited and music-filled time with the roommates. There will be a fifth year,” Berger promises, “but we haven’t decided where. We’re always trying to raise the bar.”

“London was a natural step for us,” says George Verschoor, the show’s producer and director beginning with “Real World” Loft No. 1.

“We wanted to challenge the format a bit more and add to the chaos by taking it to an international scale. Are people this age the same whatever passport they have? Also, by addressing cultural issues, we thought we could shake up American youth. Americans are so provincial and insulated. We’re showing them there’s a busy world out there. Go check it out. There’s a cool youth scene.”

Can Americans, Brits, Germans and Australians cohabit successfully? Eighteen weeks into the “experiment” in custom-built surroundings--a storefront storage shed/flat converted into a luxury four-bedroom apartment--the answer seems to be yes. It’s not possible to find out for sure because the cast is unavailable for consultation while the experiment is in progress. But one can be a voyeur, sitting in the control room in front of a bank of monitors while the gang hangs out together on this June Friday night.

“We don’t get involved with the cast,” says Verschoor, the second-oldest crew member at 36. “We let them lead their lives, and we don’t mess with them. We let them fail or succeed on their own terms.”

Verschoor’s domain is the back half of the long, narrow, two-story structure, where crew members staff an office and keep an eye on what’s going on on the “set.” The two areas are separated by locked doors. “We shoot 70 hours a week,” he explains, “and we edit as we go. We’re dealing with issues of love, respect, health and professional aspirations. Eighteen to 24 is a period of transition. You think you know everything, but you know very little, and we’re watching you discover things.”

About 20,000 candidates applied to be part of the London shoot. “We wanted people who tend to be the life of the party,” Verschoor says. “Those who could be interesting enough to sustain your attention for 20 weeks while living their own lives.” After evaluating possible combinations, he and executive producers Mary-Ellis Bunim and Jon Murray settled on:

* Jacinda, 22, from Australia: a Paris-based model.

* Jay, 19, from Portland, Ore.: a playwright and Presidential Scholar.

* Kat, 19, from Tacoma, Wash.: an NYU student and fencer.

* Lars, 24, from Germany: a University of Berlin student and music lover.

* Mike, 21, from St. Louis, Mo.: a car racer and fraternity man.

* Neil, 24, from England: an Oxford University graduate and musician.

* Sharon, 20, from England: a singer-songwriter.

“The Americans are completely detached from their support systems,” Verschoor says. “Some have held up, some haven’t. You’re off on your own--you against the world. There’s been a struggle to start life here and accomplish goals without anyone from their peer group. Londoners don’t always appreciate the excessive optimism of Americans.”

Coordinating producer Matt Kunitz, 26, contacts roommates daily to get their schedules, and then plans the day’s shooting accordingly. In addition to filming in the house, the crew has followed Mike to the Midwest for a car race, Jacinda to Milan for a modeling shoot, Kat to the Junior Olympics and Jay back home to visit his girlfriend.

“We’re really a young crew, so we can relate to our subjects,” Kunitz notes. “Say it’s 2:30 in the morning and I’m supervising a shoot in a nightclub. I enjoy it. What’s interesting to us will be interesting to our audience. Tonight we’ll be here until 4:30 a.m. because generally someone’s up till then. You never know what you’ll see. We’ve got two cameramen and two sound men filming, plus surveillance cameras in every room. [Each roommate also wears a microphone.] We can see what’s going on everywhere and decide if it’s worth filming.”

In the control room, five crew members stare compulsively at the screens looking for action, while Verschoor or Kunitz occasionally issue instructions to the cameramen via walkie-talkie. So far, there have been a few funny comments and several incidents with Jacinda’s non-potty-trained dog, but no one yet knows if they’ll end up in one of the 22-minute episodes.

Kat lies on the floor playing with the cat, then wanders off to make a phone call. Mike sits around the living room in a towel waiting to take a shower. Afterward, he and Jay shoot a game of pool. “Jay is the Jimmy Stewart of our cast,” Kunitz says. “It’s his first time away from home. He’s a polite observer but pretty witty when he wants to be.”

Currently there are no cast romances, but there’s always that chance. Tonight Jacinda, the Australian model, has a new perm and extracts a near-noogie from blond, punky Neil on the sofa. “You’re like a poodle,” he remarks, patting her head. She positions herself alongside him and half-whispers, “You’re big and buff--what I always wanted in a guy.” Neil doesn’t respond. The production notes say he has a girlfriend.

Jacinda slinks off and walks her dog. The cameraman wanders off. Neil remains incumbent. The cameraman returns. Neil stares at the ceiling and murmurs into the microphone attached somewhere under his T-shirt and black leather trousers, “It’s almost worth 20 weeks’ social experiment.”

Neil, the musician, does have a wild side, though. “One night Neil was doing a gig, and he went out into the audience and kissed a guy,” Verschoor says. “He stuck his tongue in the guy’s mouth and almost got it bitten off. He had to have 24 stitches. His tongue swelled up, and he couldn’t talk for three weeks. Neil has a sharp tongue, so it was like he was declawed.”

“The Real World” airs Wednesdays at 10 p.m., repeating Saturdays at 6:30 p.m., on MTV.