It started with a man called "Ice Cream."

Barry Wayne Toombs, a rotund man who ate chocolate chip ice cream by the tubful, gave the government its first clue in 1983 that two brothers from McLean were making millions by selling marijuana and hashish.

Last month, two years and 40,000 detective man-hours after Toombs had been convicted in Alexandria of smuggling $75 million worth of drugs into the country, federal prosecutors forced two more drug millionaires behind bars, Robert and Christopher Reckmeyer.

And the investigation is not over.

As the Reckmeyers sit in the Fairfax County jail awaiting sentencing for distributing almost 300 tons of drugs, federal agents are digging in nearby Maryland looking for rubies, kruggerands and cash -- the profits of the drug ring that allegedly sold $100 million worth of drugs in 11 years.

Federal marshals meanwhile are guarding Shelburne Glebe, the historic 1,000-acre Loudoun County estate near Leesburg that served as headquarters for the operation. It is costing the government $12,000 a month to maintain the sprawling farm, feeding its herds of goats and Angus cattle in the hopes of selling the estate to recover the costs of the investigation, one of the most extensive the government has run in the Washington area.

The brothers' ring was a classic large-scale drug operation, say federal investigators. All the elements to a movie plot, The Anatomy of the Successful Drug Enterprise, were there: the multiple South American smuggling lines, the trusted "lieutentants" who handled the cash transactions, the truck drivers and "stashhouse sitters" who were shared with Toombs and others.

While the brothers have claimed in court that prosecutors exaggerated the size of their operation, law enforcement officers say otherwise. "These guys," Con Daugherty of the Drug Enforcement Administration recently told the Associated Press, "were the Rockefellers of the marijuana business."

And like most major drug operations, which are intertwined with others out of necessity, the Reckmeyer empire was eventually destroyed by the sources it had needed to survive. "You need three or four major suppliers in order to thrive in the drug world," said Roger Ray, U.S. marshal for the Eastern District of Virginia. "Because if someone says to you, 'Sorry, I couldn't get the stuff today,' you're out of business if you turn around and tell your customers that."

Toombs, the Fairfax County man who smuggled boatloads of South American marijuana for the Reckmeyers in the late 1970s, agreed to tell authorities what he knew about other drug rings in exchange for a reduction in his life sentence, says Assistant U.S. Attorney Karen P. Tandy. Convicted in 1983 in another major Northern Virginia drug case, Toombs could be paroled as early as next year because of his cooperation, according to his attorney, Thomas C. Green of Washington.

"It's all so connected," said Tandy. "Once you begin watching one organization, you get information about others."

Tandy, who directed the government prosecution of Toombs and the Reckmeyers, cites several other examples of how the two rings were, at times, concentric.

One of the alleged kingpins in the Toombs case, Leon D. Harvey of Fairfax, who is still a fugitive, is wanted on charges of distributing drugs with the Reckmeyers. In addition to sharing dozens of Washington area "stashhouses" for their drugs, Tandy says, the two rings employed the same pool of "little crooks," individuals who served as warehouse guards and businessmen who helped launder the profits.

Securing testimony from the "little crooks" was critical, Tandy says, because most of the criminal activity had occurred before a Justice Department Organized Crime Drug Enforcement Task Force decided to investigate the Reckmeyers.

"The majority of the witnesses the government had have been users of speed, heroin and cocaine," said John Dowd, Robert Reckmeyer's attorney. "They were up against the wall and facing life imprisonment."

Tandy said she realized that the testimony of such individuals probably would not be enough in court, so a paper chase began.

Many of the documents were subpoenaed from the brothers and their numerous companies by an Alexandria grand jury.

In all, the investigators sifted through 50,000 documents to corroborate informants' testimony. "We subpoenaed all their financial records to see if they had a valid income to match their purchases," said IRS investigator James Meckley.

"That was one of Chris' problems," said Stanley Reed, Chris Reckmeyer's attorney. "He had so many visible assets, he had hundreds of cattle and a farm worth about $3 million. You just can't bury those in the ground."

Then the investigators interviewed customers of the Reckmeyers' rug, gem and organic foods businesses to see if the companies' sales were legitimate.

"It was like a puzzle, trying to figure where the money was coming from and where it was passing," said Meckley, who tracked some of the profits to Liechtenstein, the Bahamas and the Netherland Antilles.

Some of ring's profits may never be found, investigators say, but the IRS has filed property liens against the Reckmeyers seeking $72 million in back taxes and fines.

Customs agents also were alerted to the Reckmeyers, their aliases, and their employes. When Steven Scott Johnson, a courier in the Reckmeyer operation, entered a Miami airport from the Bahamas on Aug. 2, he was searched and $99,700 was seized in his false-bottomed suitcase.

"Once you're caught red-handed and realize that you're going to be facing nothing but walls for a long, long time, these guys always start talking," said Ray, the federal marshal.

Robert Reckmeyer, facing a possible life sentence, plea-bargained with the government March 13 in exchange for a 10- to 20-year term. His brother agreed to a similar arrangement the next day.

"They cracked this case by climbing up the ladder," said Toombs' attorney, Green.

"They had the little guys and they gradually worked their way up to the real money."