A few weeks ago, a friend needed to go from Los Angeles to Hong Kong and Bangkok. His travel funds were limited. He had no time to purchase a restricted discount ticket from any of the major airlines that fly the route.

Instead, on the advice of a friend in London, he flew a strange route: People Express from Los Angeles to London, and British Caledonian from London to Hong Kong. The trip took 12 hours longer, but it saved him $400.

He bought his People Express tickets in the United States. He bought the discount Hong Kong tickets from a bucket-shop in London.

No airline or U.S. travel agent officially acknowledges their existence, but bucket-shops offering incredible cut-rate fares can be found throughout Britain and Asia. The savings they offer against published air fares is, to say the least, substantial.

Bucket-shops began booming in the mid-1970s. Before that, about the only way to undercut established international fares was to form a bogus special-interest group and benefit from reduced group fares. Still, there were empty seats on airplanes.

So the bucket-shop was born to fill a distinct need: to sell those unsold seats -- a highly perishable commodity -- before the flights took off. (The name comes from an old European stock-exchange expression for dealers who traded in the sale of large quantities of nearly worthless stock peddled by the "bucket load.")

The law of supply and demand has forced the more competitive airlines to get rid of their extra tickets in some way. No airline can sell all of the seats on all of its flights. So, rather than having 100 empty seats on a flight from London to Madrid, the airline will sell those 100 seats to a bucket-shop at a discounted rate.

The problem for the airlines began in the 1970s when they started using large wide-bodied aircraft such as the Boeing 747 and the DC-10. The new planes opened the world to volume travel, but the potential for large blocks of empty seats also increased. That potential was realized shortly thereafter. In 1983, about 222 million seats went unfilled on scheduled flights by members of the International Air Transport Association (IATA). At the same time, IATA estimated its member carriers were losing $1 billion annually to illegal, discount tickets. The airlines have never been permitted by IATA rules to discount their own tickets, but deregulation has spurred competition and more seats are now turning up in the hands of bucket-shop operators.

Bucket-shops have a seedy image, to say the least. Some operate out of back rooms or on the second floors of unlikely-looking buildings. In London, since bucket-shops are not licensed, their advertising is usually done by handout flyers or word of mouth. In Taipei and Bangkok, many travel agencies are, in fact, bucket-shops.

The response from the public has been tremendous, and now even respectable British travel agencies are starting to sell discounted tickets in order to compete with the bucket-shops and stay in business. In the United States, most travel agents still refuse to acknowledge the existence of the shops, because they are required by agreements they sign with carriers they represent not to sell tickets below the minimum applicable published fares. If they break the agreement, they can lose the right to sell an airline's tickets.

For the traveler it is often -- but not always -- better to buy a discounted ticket from an experienced travel agency overseas rather than a bucket-shop (though agencies can rarely give the same high discounts), because if the company goes bankrupt you stand a better chance of getting your money back. Once the bucket-shop, or any agency, provides you with a bona-fide ticket written on a form that carries the legitimate imprint of a functioning airline's "plate," your investment is safe -- as long as you comply with the restrictions printed on the ticket and the airline stays in business. (Often bucket-shop customers receive a voucher, which they exchange for the actual ticket at the airport on the day of departure.)

Last year, Destinations 2001, a bucket-shop in London, offered a round-the-world ticket for less than $1,000. The company should have been called Destinations 1984, because that's the year it went out of business.

However, another London bucket-shop located at the same address, called Worldwide Cheap Travel (441-373-6465), is now offering a round-the-world ticket for an incredible 700 pounds (about $750).

Bestways Travel (441-930-3985) has been in the bucket-shop business for more than 14 years and specializes in discount offers to Africa. Currently, Bestways offers a round-trip to Cairo with no restrictions for 225 pounds (about $240), and from London to Bombay round trip for 400 pounds (about $430). (The regular fare to Bombay is about $790.)

Officially, there's not an airline that admits to using bucket-shops. Says James Arey, system director of public relations for Pan Am, "We have a published tariff and we have regular commissions that we pay travel agents that we must follow. We sell our seats to individuals, to travel agents recognized by IATA and to large wholesalers. We deal with legitimate wholesalers, not bucket-shops."

"KLM Holland's national carrier does business exclusively with officially operated ARC and IATA travel agents," says a spokesperson for KLM U.S. "However, it may be possible that one of these agencies might use bucket-shops as a sales outlet, which they are not authorized to do by KLM."

"People always go for the best deal since society is so price conscious, but we don't use them because they sell at less than an attractive price to us," says June Lane, British Caledonian Airways Western U.S.A regional sales manager. "They do not give a fair rate and we won't go down to that level. We would go out of business if we used them."

So, of course, there is no official explanation of how anyone can go to a bucket-shop and buy a discount ticket today on Pan Am, KLM or British Caledonian -- unless you talk to the owner of a bucket-shop.

"I've been in the business for 25 years," says Roger Tovey, owner of Travelers Airline Services (441-402-3301) "and the airlines have always been very willing to work with me. They all claim they don't recognize bucket-shops." The Londoner laughs. "But if they didn't where would we get our tickets? If we sell you a cheap ticket on Pan Am, TWA or British Airways, how could we do it without the participation of the airline?"

One ticket offered by Tovey is a real service to last-minute travelers. Every APEX (advance purchase, excursion) ticket offered by airlines requires two to three weeks' advance booking and payment. However, Tovey and other bucket-shop operators will sell you a backdated ticket for immediate travel.

"I can sell you an APEX ticket to the States right now," says Tovey, "and I do it with the airlines' knowledge and permission."

Tovey also sells discounted first-class and business-class tickets.

Other good bucket-shop deals: Impulse Travel (441-935-5364) sells London-to-Rome tickets for 100 pounds (about $108), Vienna for 130 pounds (about $140), Venice for 160 pounds (about $170) and Barcelona for just 88 pounds (about $95). These are round-trip tickets. Sun and Sand Travel (441-439-2100) offers Zurich tickets for 85 pounds (about $91) and Frankfurt for 65 pounds (about $70).

It is really not against the law for you to purchase a ticket from a bucket-shop and in most foreign countries nothing is being done to stop the practice. One exception is West Germany. There the government conducts raids on discount travel agencies to protect Lufthansa.

But, more often than not, everyone seems to look the other way. "There's a feeling that if you've taken the time to do your homework," says one bucket-shop owner, "then you deserve the ticket." As a result, published fares may be only a guide.

Even IATA appears to have thrown in the enforcement towel. A few years ago, in a celebrated case, the association levied a stiff fine against one Asian carrier, Air Siam, for illegally discounting tickets.

Since then, IATA seems only to report on the problem. "We are not policing this market anymore," says Josephine Peach, a spokesman for IATA in Montreal.

"The cleanup efforts are conducted by the airlines themselves and by local groups," she says. "The local boards of airlines are responsible for examining the practices that are against the rules."

In 1982, IATA adopted a relatively weak resolution giving the president or chief executive of an airline the responsibility of taking action to end illegal discounting and "personally supervise the tariff integrity of his own airline in the markets his company serves." These leaders are also supposed to meet "periodically to take adequate action within (their airlines) to help insure tariff integrity." There is no mention, however, of disciplinary actions to be taken if the resolution is not followed.

This was changed at IATA's annual meeting in 1983, when surveys showed that the program had produced an improvement in only 18 percent of the markets and that 28 percent had actually gotten worse. Thus the delegates voted to incorporate sanctions into the enforcement effort.

If you are in the market for a good bucket-shop, but you're not sure how to find one, Frank Barrett's "A Consumer's Guide to Air Travel" (published by the London Telegraph) might help. Barrett gives a list of reliable bucket-shops that shouldn't leave you stranded at the airport without a legitimate ticket.