For years, he had his mind...

Gregory Freeman Stone’s last day began with business as usual.

That morning he talked with friend and next-door neighbor Floyd Nelson about the mission that had consumed more than a decade of his life: reopening the official investigation into the 1968 assassination of Robert F. Kennedy.

For many who knew him, Stone was an “unsung hero,” a man attempting to “rewrite history.”

To them he was a valiant swimmer against the mainstream of American politics, a scholar and researcher buoyed by democratic idealism and a love of truth. Above all, the former protege of Allard Lowenstein was a white knight who would help finally resolve their lingering questions about whether Sirhan B. Sirhan acted alone in the death of Robert Kennedy.

Indeed, Stone’s associates noted that he was a veteran behind-the-scenes political operator and a master researcher adept at marshaling facts and coaxing information from bureaucratic nooks and crannies. Some give him a key role in the 1988 release of the Los Angeles Police Department’s voluminous files on its investigation of the Kennedy killing, a milestone for those determined to pursue the case.

But the neighborly chat with Nelson was a facade.

Over the past few days, Stone, 41, had been calling friends around the country, including crime reporter and author Dan Moldea in Washington, D.C., and actor Paul LeMat in Los Angeles, both members of a small circle of assassination skeptics who supported Stone’s work. The conversations were lengthy, up to 45 minutes, and seemed more or less routine.

In retrospect, the calls resembled codes that could be broken only through hindsight.

“He was saying goodby to me,” LeMat recalled. “He was apologizing for not doing more, he was being very gracious, saying, ‘Thanks for all your help, your donations and your time. I think you’re extremely decent.’ He made me feel good, very good.”

LeMat, Nelson and Moldea knew that Stone was depressed and had been for months. Stone had been complaining that he lacked the energy and willpower to continue his self-assigned task, that he needed to get away from the Kennedy assassination, perhaps complete studies for a doctorate in political science. If he had ruined his academic credibility with his assassination work, he could always get a job at McDonald’s, he would sometimes joke with a tinge of bitterness.

But no one guessed that Stone had reached the end of his rope, that he was terminally disappointed, with himself and with the public and official response to his investigations.

Then, on the afternoon of Tuesday, Jan. 29, Stone--universally described as self-controlled, iron-disciplined, supremely rational, brilliant, compassionate--drove his battered red Volkswagen from his drab, file-packed Hollywood duplex to the Fern Dell section of Griffith Park, chose a spot under a tree, sat down, put the barrel of a Smith & Wesson .38-caliber revolver in his mouth and pulled the trigger.

Stone’s body was found almost immediately by a park worker, said William Sheffield, an investigator for the Los Angeles County coroner’s office. Police arrived minutes later, retrieving a note near Stone’s foot that directed them to his car parked a couple of blocks away, Sheffield said. Police found three other notes, two on Stone’s body and one in the car asking that Floyd Nelson be notified of his death.

Everyone who has seen the notes says they were apologetic. Stone expressed regrets that he “had let down his friends and associates and family,” Sheffield said.

Later that day, Nelson found another note at Stone’s duplex, in a file labeled “post mortem.”

It read: “This is my own decision and comes out of my own problems and shortcomings. It is not the fault at all of my family, friends and the people I’ve worked with.

“I’m sorry to have let my family and so many others down.”

In the wake of Stone’s death, as his friends and family discussed his life, it became increasingly clear that the shy, self-effacing man kept a vital part of his soul shrouded from even his closest associates. None knew he had recently acquired the revolver, for instance. Nor did they know he had started taking Prozac, a controversial anti-depressant drug that has been linked to suicide. LeMat and Nelson said they discovered vials of the drug, prescribed by a doctor, in Stone’s apartment the day after his death.

“I think a lot of us feel we had a very close professional relationship with him,” said David Mendelsohn, an award-winning New York City documentary filmmaker who sometimes helped Stone in his investigation. “I guess on an emotional level I didn’t know him very well.”

Stone’s suicide--as it was ruled by the coroner and accepted by his friends--set off an expanding wave of grief and bafflement.

“I view suicide as almost being an unforgivable sin,” Moldea said. “I just don’t understand.”

Alongside their incomprehension, however, Stone’s friends harbored feelings of love and respect.

“I remember Greg repeating over and over, ‘We’ve got to do something in this country where leaders are being assassinated. We’re operating like banana republics in terms of choosing our leadership,’ ” said Paul Schrade, a former labor official and friend of Robert Kennedy who was also wounded in the shooting at the Ambassador Hotel. “I think as a political scientist and as a human being he felt that the assassinations (of the 1960s) were more than just one-gun, lone-nut operations.”

Moreover, the Kennedy killing was not the only political death with which Stone was intimately familiar. Stone’s mentor and one-time employer Allard Lowenstein, an educator, former New York congressman and maverick Democratic Party activist who was close to Robert Kennedy, was gunned down in 1980 by Dennis Sweeney, a former student. It is an ironic historical footnote that just before he was shot, Kennedy had reportedly been trying to call Lowenstein. In the same vein, some believe that Sweeney was not acting on his own when he shot Lowenstein five times.

Stone, who worked with Lowenstein from 1969 to 1976, was one of a legion of young, idealistic “volunteers/employees” who rallied to Lowenstein and his causes, recalled Lowenstein’s ex-wife, Jenny Littlefield, a psychiatric social worker in the Washington, D.C., area. Stone and Lowenstein continued their association until Lowenstein was killed, she added.

Beginning in 1973, Lowenstein found himself reluctantly but irresistibly drawn into the controversy surrounding Robert Kennedy’s death. His odyssey was described in an article, “Suppressed Evidence of More than One Assassin?,” written by Lowenstein for Saturday Review magazine but generally considered to contain major contributions from Stone. In the article, Lowenstein admitted that he met with a group challenging the official version of Kennedy’s death simply to display an “open mind.” But as they presented their arguments, he was convinced that the case needed to be renewed.

In homage to Lowenstein, Stone helped collect the Saturday Review article and other pieces, essays and speeches for a book, “Lowenstein: Acts of Courage and Belief,” published in 1983. The book also contained Lowenstein’s unfinished assessment of Robert Kennedy, with a passage on political assassinations often cited by Stone:

“What is odd is not that some people thought it was all random, but that so many intelligent people refused to believe that it might be anything else. Nothing can measure more graphically how limited was the general understanding of what is possible in America.”

It was Stone’s close relationship with Lowenstein and the Kennedy case that ultimately led to his decision in 1985 to drop his doctoral studies at the University of Wisconsin and devote all his time to the then-17-year-old case, friends said. He moved to Los Angeles, living with acquaintances until he rented the duplex next to Floyd Nelson. He lived off a small inheritance and occasional donations from friends.

In those years, Stone threw himself into his investigations with an intensity and devotion that several friends described as “monk-like.”

“This case was his religion,” Moldea said, adding, “You could not have a conversation with him for five minutes without him bringing up this case.”

Over time, Stone’s small, narrow duplex came to resemble a cross between a shrine to Robert Kennedy and an archive on the senator’s murder. A poster of Kennedy held pride of place in the front room and was one of the few bright spots in a deluge of brown, beige and gray.

Stone packed his apartment with filing cabinets, a word processor, a copier, a microfilm reader and hundreds of books on Kennedy, politics and related subjects. Aside from a college diploma and a poinsettia left over from Christmas, there were few personal touches. On one wall, Stone hung a schematic drawing of the assassination scene at the Ambassador Hotel. By the end of his life, the accretion of files, books and newspapers had turned the dimly lit duplex into a maze that had to be negotiated with care.

In this confined, ascetic environment, Stone spent much, if not most, of his time. Several friends recalled that no matter when they dropped by, they would find him working at his desk, searching for one more angle to exploit, one more hidden clue.

And from this unlikely base Stone mounted a campaign to compel one more official look at the death of the 42-year-old New York senator who was campaigning for the Democratic presidential nomination.

It was a formidable task.

Robert Kennedy was mortally wounded at 12:15 a.m. June 5, 1968, just after acknowledging his victory in the California primary. He died nearly 26 hours later, after brain surgery, at Good Samaritan Hospital.

Officially, the only suspect was Sirhan B. Sirhan, a 24-year-old Palestinian immigrant who was apprehended at the scene and later said he acted alone. He was convicted of the murder in 1969 and remains in a California prison serving a life sentence.

Since then, however, a school of thought has evolved that a second gunman might have been in the kitchen pantry where Kennedy was shot. Official and unofficial inquiries into this possibility failed to resolve the matter to the satisfaction of some skeptics--although many others were convinced that the case for a second gun was almost non-existent.

In many ways, the aftermath of the Robert Kennedy assassination mirrors that of his older brother, President John F. Kennedy, in 1963 in Dallas. That killing has sparked a mini-industry devoted to challenging the official conclusion that President Kennedy was the victim of a lone gunman, Lee Harvey Oswald.

Likewise, almost from the day Robert Kennedy was shot, a persistent band of doubters has questioned the official verdict on the senator’s death. Although smaller and much less visible than the army that has attacked the official story on John Kennedy’s killing, the Robert Kennedy skeptics have struck at alleged discrepancies in testimony and purportedly mishandled, overlooked or ignored evidence.

Stone, his friends say, entered this swamp of disputed evidence and theory determined to make an indisputably objective survey of the facts. Indeed, he seemed perfectly suited for the task. He had been a brilliant student, graduating summa cum laude from Oberlin College in 1971. Later, he received a master’s degree in political science from the University of Wisconsin and attended law school at the University of Virginia.

Stone soon became an expert on the crime scene, gathering, collating and studying the seemingly endless reams of documents, eyewitness interviews and photographs. The assassination, he once asserted, was “the most important crime that ever occurred in the city of Los Angeles.”

One measure of his task is that in 1988 when Los Angeles Police Department files on the case were released, they contained more than 50,000 documents, photographs, tape recordings and pieces of physical evidence.

Near the end of his life, Stone was focusing on test-firings into pieces of wood that replicated door frames in the Ambassador Hotel pantry. The test-firings were an attempt to match crime-scene photos that many believe show bullets lodged in the door frames. Stone considered such a test necessary because actual sections of the hotel door frames that might have contained bullets or bullet fragments were destroyed about a year after the assassination.

If, somehow, Stone could prove that bullets had struck the door frames, he would have proved that more bullets were fired than the eight in Sirhan’s .22-caliber revolver. Sirhan’s eight bullets have been accounted for by the Los Angeles Police Department. Investigators said three bullets struck Kennedy and the other five struck and wounded five other people, all of whom survived.

In the process of his study, Stone became “the most knowledgeable person in the United States” on the Robert Kennedy assassination, in the opinion of John Burns, chief archivist for the state, which now holds the case files. But Stone was not, his friends insist, a wild-eyed conspiracy theorist of the type who have produced fanciful explanations for other assassinations. Rather, they say, he was a perfectionist who insisted on meticulous work from himself and others. In fact, several friends and acquaintances spoke of Stone’s “high standards,” a demanding, self-imposed yardstick that made it almost impossible for anyone, including Stone, to measure up.

“He didn’t give himself much leeway,” said his sister Jennifer Stone, a psychologist in Starkville, Miss.

“He was always worried that he might not be doing something right,” said Burns, who got to know and respect Stone during his trips to Sacramento to look at the Kennedy files. “What he repeatedly said to me was that he didn’t know what happened and that’s what disturbed him so much. He had no predisposition to a conspiracy or that there were multiple gunmen. What he wanted more than anything else was a new investigation.”

Moreover, Stone often put the brakes on speculation among his colleagues. “He took a very objective view of this assassination,” said actor LeMat, whose movies include “Melvin and Howard” and “American Graffiti.” “He insisted we have to answer these questions . . . . And I’m saying ‘Well, hey it was a conspiracy, it was the CIA, hey, hey.’ And he’d say, ‘Well, we don’t know for a fact any of those things.’ ”

Neighbor Nelson, who wrote an early article on the second-gun theory for the Los Angeles Free Press, recalls that Stone once quoted a poem by Robinson Jeffers to caution him against flights of assassination fantasy.

The poem, “Be Angry at the Sun,” reads in part:

That public men publish falsehoods

Is nothing new. That America must accept

Like the historical republics corruption and empire

Has been known for years.

Be angry at the sun for setting

If these things anger you. . . .

In 1990 it began to look as if Stone’s laborious research was about to pay off. After years of preparation, Stone and his associates launched last spring the offensive they hoped would spark an official reinvestigation.

On May 13, the Washington Post published in its Outlook section an article by Moldea pointing to the possibility of more bullets--at least nine and as many as 12--being fired than could be accounted for by Sirhan’s revolver.

Law enforcement officers interviewed by Moldea recalled seeing bullet holes in a door frame and possibly other sites at the scene. Moldea, whose books include “The Hoffa Wars” and “Dark Victory: Ronald Reagan, MCA & the Mob,” said Stone’s contributions were vital to his reporting.

“It was Greg who was the brains of the operation,” he explained.

Later that week, the group held a press conference in Los Angeles to present its findings on the bullet holes.

A day later, the second-gun assertion got a national airing when NBC-TV’s “Unsolved Mysteries” broadcast a segment on the Kennedy assassination.

Stone and those around him expected this three-pronged attack to galvanize Los Angeles county and city officials into taking another look.

It didn’t.

Aside from the brief media buzz, there was almost no response to the newly buttressed second-gun theory. A Los Angeles police spokesman quickly dismissed the group’s allegations as a rehash.

Stone took the rejection of his work hard, and it seemed to increase his already noticeable gloom.

“Greg was very, very down when that whole thing came to naught,” Moldea said.

“When he called me at Christmas, he sounded pretty depressed,” Jennifer Stone said. “I think one of the things that concerned him was that all the work he had done, maybe it wouldn’t go forward.” Stone had at least one other bout with major depression about 14 years ago, his sister said, adding that his childhood was marked by the unhappy marriage of his parents. “I think it made him somewhat more prone to sadness,” she explained.

Nelson recalled: “He had a tremendous sense of failure. He used to talk to me and it was self-recrimination . . . he was quite a perfectionist and he would accuse himself of being stupid. . . . The last year I thought that he was very depressed, as if he had come up against a wall.”

At least in part, Stone was deeply disenchanted by what he saw as a failure of “the system,” his friends say. But Stone’s ideals may have been too high, they add.

“I think he understood the theories of politics but I don’t think he understood the realities of politics,” Moldea said.

Intensely aware of Stone’s disenchantment, Jennifer Stone said that in one of her final talks with her brother, she urged him to “take a new approach to political science, rather than being defeated by the existing system.” Seminal thinkers, she told him, find ways to buck the Establishment in any field.

LeMat, who used to drop in on Stone, also sensed that something was going wrong, but he didn’t grasp the extent of his friend’s despondency.

“I’d joke with him and say, ‘One of these days I’ll go by there and you won’t be there. But you’ll be back,’ I said. But he kind of went, ‘Uh-uh,’ like he really wasn’t going to come back,” the actor said.

Stone also spoke of “troubles he didn’t want to talk about,” LeMat said. “He said, ‘There’s a lot going on that’s interfering with my ability to work on the case.’ ”

LeMat said he then offered to recommend a psychologist. “He said, ‘Thank you very much but I am seeing somebody.’ He turned that down.”

LeMat also offered the comfort of religion. “I’m a Christian and I have a very secure, strong faith, and I talked to him about that because I thought that would give him peace and hope for the future,” he said. But Stone “wouldn’t take that option either in terms of asking, ‘What about this, tell me more,’ that kind of thing.”

Moldea had other advice: Believing that Stone had become a prisoner of an obsession, he urged Stone to take a break. “I told him, ‘Greg, go the beach, get a tan, chase women.’ ”

Meanwhile, Paul Schrade noticed that Stone, never very gregarious, was becoming more and more of a loner. “I found that I began calling Greg, where I always knew that he was going to call me a couple of times a week,” Schrade said.

Even those who didn’t know Stone well sensed that something was wrong. David Lifton--a writer best known for “Best Evidence,” a book about John Kennedy’s assassination--met Stone for breakfast about a week before the suicide. “He looked in anguish and in pain,” said Lifton, adding, “There was the scared, trapped animal look in his eyes.”

After Stone’s body was released by the coroner’s office, it was shipped back to the family’s home in Otway, Ohio, where a funeral was held Feb. 5. In Los Angeles, friends gathered for a small memorial service last Sunday.

In the aftermath of his death, assessments of Stone’s life had a similar ring.

“People as a society don’t want to look at things that are upsetting and Greg was looking at a lot of things that are upsetting,” his sister said.

“If Greg had any fault, it was he paid too much homage to the truth and doing things right,” Nelson said.

And Carol Moss, who gave Stone a room when he first came to Los Angeles, remarked that Stone was “brilliant and careful and caring and he got nothing back for it and it was lethal.”