They were boys, American teens of the 1950s, when they met. The year the Russians shot Sputnik into the skies, Jerry Whitworth and Roger Olson said hello at a naval shipyard in San Francisco and began a friendship that would last longer than either of their Navy careers.

Olson spent just two years in the Navy. After he spent 15 years as a high school teacher, his love of sailing led him to Papua, New Guinea. Whitworth, quiet, yielding, looking for some "kind of direction" as his friend would say, decided to stay in the Navy.

He advanced well, gaining seniority as a radioman, adding to his monthly paycheck and making friends easily with coworkers and superiors. "I consider him Whitworth my best friend . . . a quiet, compassionate man I've known for 28 years," Olson said.

When Whitworth left the Navy in 1983, he had a wife and no job, Olson remembers. He also had a special relationship with one of his former shipmates, John Anthony Walker Jr.

"Have you ever seen an aggressive used-car salesman? That's Johnny Walker," said Olson, reached by telephone at his home in New Guinea. "Jerry knew John Walker and knew him quite well. When I met Walker, I just didn't like him. He was calculating, a finagling type of individual. He would dominate, just make you feel inferior.

"I was always surprised Jerry and John Walker were friends. I felt very close to Jerry and I thought we had no secrets," Olson said. "Obviously, if what everybody's saying is true, there was one very big secret."

That secret, federal prosecutors charge, was that Whitworth was a spy for the Soviet Union. And he did his work, they say, as an accomplice to Walker, who is alleged to be the linchpin in a 20-year conspiracy to divulge sensitive military secrets and documents to the Soviets.

The extent of Whitworth's alleged complicity remains largely unknown. And, in a case laden with mystery, the bearded, studious-looking Whitworth has remained the most enigmatic of personalities.

Unemployed, a 45-year-old house-husband of sorts, Whitworth had recently moved to a mobile home near the University of California at Davis so his wife could pursue a doctoral degree in nutrition. His neighbors, older retirees, say they don't know him.

His wife, Brenda, a soft-spoken, polite woman who has turned down interview requests, has released only a brief statement about her husband. Whitworth is a man, she says, whom she believes in and still loves very much.

Family members and friends in the farm town of Muldrow, Okla., Whitworth's birthplace, recount tales of a younger Whitworth, a "sweet boy" who was voted the class clown at Muldrow High and who left home at age 17.

But what was Jerry Whitworth, the adult sailor, like?

This week, the Olson family of Fresno, Calif., talked about the boy they came to love in an attempt to provide a picture of a man who they said was an unlikely candidate to commit espionage.

Addie Olson, who cooked hot dinners and washed laundry for the young man her son Roger brought home from the base one day, says she can't believe he is a spy.

"He's a very quiet, refined man. This just isn't in his character at all," Olson said. "Six years ago, when Roger moved to New Guinea, Jerry knew we were so lost without him. Jerry started calling once a week. He visited on weekends. When I had to go into surgery, Jerry came to my hospital room. He's no more like Johnny Walker than night is to day."

Olson described Whitworth as a "lost soul" during his first years in the Navy. Her son remembers Whitworth as someone who became a career Navy man because he wasn't sure what to do with his life.

During a career that spanned two decades, Whitworth quit the Navy three times -- to try college, then a catering business, then to sail around Mexico -- but always returned after a few months, Roger Olson said.

In the late 1960s, Whitworth was Olson's buddy and seemed "easily influenced" by what other people said. "When we were younger, Jerry never argued. He would discuss things but usually end up having the same opinion as me," Olson said. "But in the last 10 years, he has become more independent."

It was during those younger years that Whitworth and Walker became friends, Olson said. He remembers that the three of them went sailing one day in San Francisco Bay. Later, Olson met Walker again at Whitworth's house in San Diego.

After both meetings, Olson recalls telling Whitworth that he didn't like Walker, who was the assistant director at a radioman school at the Naval Training Center in San Diego from September 1969 to December 1971. Whitworth was an instructor at the school from October 1970 to January 1973, according to Navy records.

"Jerry kind of made it a point not to have John Walker around when I was around. John Walker would brag about anything and everything," Olson said. "I remember once that Jerry said John was making a killing in the car radio business."

That business, known as Walker Enterprises of Virginia Beach, was incorporated in 1975 by John Walker and his brother Arthur, according to Virginia records. A lien was placed against it by the Internal Revenue Service in 1981 for failure to pay taxes. The firm has been dissolved, according to state incorporation records.

It was also during the late '60s that Whitworth married for the first time, Olson remembers. The marriage was to Evelyn Woodhouse, a woman as vivacious as Whitworth was quiet, he said. It ended in divorce 10 months later. The two didn't keep in touch, Olson said. Woodhouse died in a car accident in 1974, two years before Whitworth married Brenda Leah Reis.

To Roger Olson, Whitworth was the kind of friend he could confide in. They wrote letters whenever the other was away on a tour. For the past six years, the two have communicated through cassette tapes, hour-long audio letters that would arrive in New Guinea twice a month from Whitworth, Olson said.

In those tapes, Whitworth never made a reference to spying, Olson said. In the tape that Olson received just last week -- mail delivery from the United States takes two weeks -- Whitworth does not speak of the 24-hour surveillance that the FBI said it began on his home or the two searches agents made on May 20 and May 31, Olson said.

Instead, he said, the tapes over the past few years reveal a man who speaks of love and respect for his wife; who was an avid reader and was studying to be a stockbroker; who was attracted to Gary Hart in the last election but still deemed President Reagan his favorite.

The tapes are from a sensitive quiet man, Olson said, a man who was so private that he kept his wedding to Brenda Reis a secret for three years. "They just wanted to maintain their own identities and their own lives without us knowing," said Olson, who still has the invitation the couple sent for their wedding reception.

According to that invitation, the semiformal wedding reception was held at the Hotel del Coronado in San Diego. The reception was held May 12, 1979. The ceremony, according to the invitation, took place May 24, 1976.

Olson remembers the reception as a small party -- and a gathering that included John Walker.

"Jerry defended John Walker to me often. Often," Olson said. "Jerry would say, 'You just don't know him. If you knew him, you would like him.' "

Over the years, Whitworth would talk about John Walker's family, referring to his daughter Laura Walker as a "beautiful girl." But Olson said he "didn't think" Whitworth had ever met Arthur, Walker's brother, or Michael Lance, Walker's son, who also have been charged with espionage in connection with the case.

According to an FBI affidavit, Arthur Walker has said he was "aware that Jerry Whitworth was involved in the espionage ring and had supplied Walker with classified information." John Walker was encouraging his brother to "operate like Jerry, who was making 'big bucks' by photographing classified documents in his van and then supplying them to Walker," the affidavit says.

"John Walker would visit Jerry once or twice a year and Jerry would visit him, too," Olson said. "But Jerry didn't have a lot of money. When he would go back East, he would always drive rather than fly . . . . Jerry knew how to sail and how to fly a plane -- he was a very good pilot. But he never owned a plane or a boat. He owned absolutely nothing. He was never frugal -- but he never had lots of money."

According to tax records in Alameda County, Calif., Whitworth and Reis once owned a condominium in San Leandro. That property, which they bought in 1978 at a cost of $46,000 with a 30-year mortgage, was sold by them in 1983, records show. Neither Whitworth nor his wife are now listed as property owners, according to Alameda County records. They now rent their mobile home in Davis.

Whitworth liked to play the stock market, Olson remembered, and said he was interested in making a career out of financial planning. In the past year, he told Olson that he had had "very, very good luck in dealing with mutual funds," Olson said.

Whitworth and his wife recently bought a computer that they told him they were using for her dissertation and Whitworth's financial studies, Olson said. FBI agents have testified that discs used on that computer, found in Whitworth's mobile home, also contained letters from Whitworth to Walker. Copies of those letters were found at the Montgomery County site where Walker allegedly dropped Navy documents for his Soviet contact May 19, according to affidavits.

"Brenda knew John Walker and at first she didn't like him either," Olson said. "But you know, on a recent tape, Jerry said, 'Roger, I know you don't like Johnny but guess what? Brenda has decided she likes him.' "