Not since Oscar Wilde dropped his famous slander case against the Marquess of Queensberry has a literary lawsuit caused so much excitement. The million-dollar libel complaint that Gore Vidal, 53, is pressing against Truman Capote, 54, pits against each other not only best-selling authors and deadly enemies, but also a pair of razor-tongued salon fighters aboil with malice. Says Capote of Vidal: "I'm always sad about Gore—very sad that he has to breathe every day." Retorts Vidal: "Truman made lying an art form—a minor art form."

The spat, legal and otherwise, springs from a 1975 Playgirl interview in which Capote charged that Vidal had been bounced from a 1961 White House party because of drunken and obnoxious behavior. Should it ever come to trial, the case could feature cameo court appearances by such eminent eyewitnesses as John Kenneth Galbraith, George Plimpton, Arthur Schlesinger Jr.—and even Jackie O herself. Capote has given a preview of the fireworks-to-come in a withering blast at the guest of honor of that ill-starred Camelot bash—Jackie's little sister, Princess Lee Radziwill, 46.

It was Princess Lee, says Capote, who told him that Gore was tossed out of a White House function. Vidal's alleged offenses: putting his arm around Jackie and insulting her mother, Mrs. Hugh D. Auchincloss. (Curiously, Gore's mother was a previous Mrs. Hugh D. Auchincloss. Guests at the party—Schlesinger and Plimpton among them—deny that Vidal was forcibly ejected, though they confirm that he squabbled with Bobby. And Lee herself—on whose testimony Truman had counted—shocked him by signing an affidavit for Vidal. "I do not recall ever discussing with Truman Capote the incident or the evening," she declared in the document. Replies Capote angrily: "She's just a treacherous lady, and that's the truth of it. She's treacherous to absolutely everyone."

What did the princess think of being caught in the quarrel? "We know what they are," she told a New York gossip columnist. "They are two fags. It is just the most disgusting thing." Incensed, Capote went on the local Stanley Siegel TV talk show to exact his revenge. "We all know a fag is a homosexual gentleman who has just left the room," he said, and went on to define a Southern fag as "meaner than the meanest rattler you ever met." Then the former Truman Streckfus Persons of New Orleans told all he knew—and perhaps even more—about the life and loves of the "dear friend" who crossed him. "I know that Lee wouldn't want me tellin' none of this," he giggled, "but you know us Southern fags. We just can't keep our mouths shut."

In a brilliantly executed soliloquy (he stayed home to prepare it the night before), Capote lit into Radziwill with ill-concealed fury. "You know, she calls herself a princess," he marveled in falsetto. "I always thought that a princess was the daughter of a king and a queen." (Radziwill's title dates back to her 1959 marriage to Polish Prince Stanislas Radziwill, whom she divorced in 1974.) The Tiny Terror—who wrote the 1968 TV adaptation of Laura to launch Radziwill's brief acting career—then rolled out his heavy artillery. He accused Lee of jealousy toward her sister ("The princess kind of had it in mind that she was going to marry Mr. Onassis herself") and claimed she once tried to woo author William F. Buckley Jr. away from his wife. (Enroute to Alaska last week, Buckley kept himself hors de combat.)

Capote went on to give his versions of Radziwill's subsequent encounters, like her break-up with photographer—and current Cheryl Tiegs escort—Peter Beard ("He met this chick with a little less mileage on her") and her on-again-off-again engagement to San Francisco hotelier Newton Cope ("She said he was simply a nobody who was riding on her coattails"). Though the princess refused to reply to the Terror's attack, Cope retaliated in full gallant plumage. "Capote has not spoken to Lee in 10 to 15 years," he announced (though Capote claims to have seen her last November). "What can you expect from a has-been writer who is all washed up and is fighting for any kind of publicity on the way down?"

Capote, meanwhile, bristles at the imputation of vengeance and projects an air of genuine sadness as he talks about the woman he considered his closest female friend for more than a decade. "You know, I was placed in an impossible situation by this whole thing," he says. "It wasn't as though I sat down and was deliberately being vindictive. She simply didn't tell the truth." He accuses Radziwill of turning sister Jackie against him, then deserting him for Vidal during Capote's lengthy struggle against liquor and pills. "I think she kind of thought I wasn't going to pull myself out of that the way I did," he surmises.

Though deeply wounded by Radziwill's "betrayal," Capote isn't considering a legal surrender. He has refused to settle with Vidal out of court, despite well over $40,000 in legal bills and Playgirl's apology and retraction of his White House party anecdote. Victory, he maintains, will be his. "I couldn't be more sure of anything short of death and taxes," he says.

Observing from his hilltop villa in Ravello, Italy, Vidal is equally sure he will win. "I have not brought this suit to make money," he says, "but I do think, pro bono publico, that the laws of libel are important and that a relentless liar ought to be, if not stopped, curbed." Truman, for his part, has taken to calling Gore the "Nixon" of a "literary Watergate," and Vidal has reciprocated with a scathing assessment of Capote's public persona. "Every generation," he purrs, "gets the Tiny Tim it deserves." However the court fight is resolved, the feud can't end soon enough for those few remaining stalwarts—like author Plimpton—who still count both Vidal and Capote as friends. "There's no venom like Capote's when he's on the prowl—and Gore's too," Plimpton says sadly. "I don't know what division the feud should be in. I don't want to say flyweight—maybe bantamweight. I wish they'd go back to having tea at the Plaza."