The rooms are dark, carpeted, air conditioned and sealed off like a vault from the outside world, a sharp contrast to most other offices in the bank. A couple dozen or so traders, most in their 30s, sit around futuristic octagonal consoles that could have been part of the set for Star Trek.

But at exactly 9 a.m., bells ring, lights go on, and television screens hung above all of the desks begin to flash the latest prices of various currencies. Within a matter of seconds, millions of dollars have changed hands.

The money traders are the pounding heart of the Euromarkets. Sometines they merely are executing orders from bank clients, but other times they are riding herd on millions of dollars of the bank's own money, buying, selling, bartering to make an extra buck from the rise and fall of a currency-any currency.

The scene is the same for all of the major banks' trading rooms, here as well as in all of the big money market centers.

Scores of highly motivated traders play a never-ending guessing game, trying to figure out how high or low a certain currency will be on a given date, or even at a given hour.

The pressure is intense. Many traders burn out after only a few years. Few asleep well, knowing that at all times someone, somewhere, is buying or selling the currencies they have invested in.

The tension in the trading room is heightened by the almost futuristic communications system that links traders with their counterparts in rooms around the world.

Each has dozens of phones lines, which at the press of one automatic-dialing button can produce a quotation on the exchange rate of one major currency against another.

"Things happen so fast in a trading room that we can't possibly keep track of all of our traders," said one New York bank officer. "We have to trust our managers to keep their traders in line, and we give them limits that they aren't supposed to exceed."

While many of the trades made in any of the major trading rooms are in response to specific transactions-the bank may need to pay off a loan in a particular currency that it doesn't have on hand, or a client company might want to sell some French francs because it has too many-perhaps half of the trades are primarily speculative.

In some cases, the real gambler sells something he doesn't have, hoping to quickly borrow to cover what he has just sold or buy it back at a cheaper rate before he has to pay off.

Unlike the public's perception of the staid international bankers poring over papers and contracts before making a move, the money traders play what may be the fastest game in the world.

Sitting back in a London pub after a tough day, two American money traders sip pints of ale and reflect on their jobs and the millions of dollars that they handle every day.

"Sure, on a quiet afternoon-specially at the end of a week-we can take some pretty strong shots and send the dollar spinning," one said. "But it won't last long. You've got to move awful fast to make that kind of money."

"Look," says the other. "They watch us pretty closely. But if you saw a real chance to make some fast money, and you didn't have time to clear it, you could exceed your limit and buy or sell a bundle. On a good day, you could even make the bank a couple million.

"But you better be right," he added quickly. "Or it'll likely be your last day on the job."