There are not many stories left buried in James Ellroy's past. In 1996, at the age of 48, he penned his memoirs, in which he paired his life story with that of his dead mother, Jean Ellroy, a nurse found strangled and beaten in the bushes of suburban Los Angeles in 1958, when her son was 10. By the time My Dark Places was published, Ellroy had told the story of his mother's unsolved murder so often it became rote; he recited it to journalists with all the passion of a man rereading his grocery list. But he had to tell the story, because it explained why he became a writer, a teller of iniquitous tales. "My death gave you a voice," Jean told her boy, from the big sleep.

He also liked to talk about how he spent his young years stealing, guzzling booze and sipping weed, spouting hollow racist jive, bouncing in and out of the Army, sniffing the panties of Los Angeles' well-to-do beav. Ellroy loved to tell those stories. They helped sell the books, his long, shorthand masterpieces about morally bankrupt men perpetrating murder and mayhem beneath the security blanket of authority and power. Among them: The Black Dahlia, L.A. Confidential, The Big Nowhere, American Tabloid, White Jazz and, now, The Cold Six Thousand. Those stories made him money, so he told them and torqued them. They gave him cred. They made his rep--the Demon Dog, barking at shadows.

But Ellroy has one last secret to spill. "It's one of the few degraded stories from my youth that I'd never told my wife," he says. Over the phone, he speaks in a soft, hushed tone, like that of a co-conspirator hatching plans, so listen up. This is the story--one more, anyway--that answers the Big Question, which is: Why, for the last 20 years, has James Ellroy brooded on crime and corruption, be it in Los Angeles, Vietnam, Dallas, Las Vegas or Washington, D.C.? He starts with the simple answer: "You get to be the guy who does it. You get to be the guy who writes the book." He means he gets to be the guy who, in The Cold Six Thousand, beats the hell out of Jack Ruby and convinces him to plug Lee Harvey Oswald in the basement of the Dallas Police Department HQ. He gets to be the guy who makes love to women who are much stronger than their weak-willed men. He gets to be the guy who kills Martin Luther King Jr. and Robert Kennedy. He gets to go to Vietnam, make heroin and bring it back to sell to the blacks. He gets to be J. Edgar Hoover. He gets to be wicked. And he gets to suffer.

But what makes a man want to wallow in such malevolence, especially a man who abhors the weak and immoral? The answer can be found in the summer of 1960. James is 12 years old. He attends a junior high full of "shtick-happy smart Jews and rich-ass WASPs." He doesn't fit, but the kids groove on politics, and Ellroy catches the virus, which hangs in the air like smog: John Kennedy, funny-looking and funny-sounding, is about to become the Democratic candidate for president. James wants to watch the convention. His pussy-hound old man says no, off to Woodcraft Rangers camp 40 miles northwest of L.A. The old man had his reasons.

"And I was reading at the time From Here to Eternity by James Jones--the epic novel about the U.S. Army in Pearl Harbor before the attack," Ellroy recalls. "It's my first adult mainstream novel I can recall reading. It's all about the corruption of institutions, it's about adult sexuality, it's about men and women and their ambiguous relationships, and it's about the unvarnished ugly world of men in general. I'm obsessed, shocked, horrified, appalled, wounded and enthralled by this book, and I can't take it with me to camp because it's a library book. The old man's got an agenda here, and I don't know what it is. He shoots my skinny ass off to Woodcraft Rangers camp, where it's a big, fat fuckin' drag. I don't wanna go swimming. I don't wanna go on nature hikes. Fuck this."

Fall arrives, and James enters eighth grade. One day he falls sick. The nurse calls home; the old man doesn't answer, so James rides his bike to the shoddy upstairs apartment he and his dad call home. The door is open. He walks up the steps. He hears grunting: "Unh-unh-unh-unh-unh." The virginal Ellroy understands what's going down.

"I walk down the hall a little bit," he continues. "I crane my neck inside, and the old man, who is 62 years old at this point, is throwing the schnitzel to a checker that I know from the Safeway, who is the mother of a classmate of mine. They're havin' fuckin' sexual intercourse, and the dog is trying to sleep at the foot of the bed with these legs thrashing all around her. I scope out the action a little bit, then I get embarrassed. I am afraid of revealing my presence up there, and I split. What this gives me is politics, contextually: Kennedy's emergence, my reading of an adult novel for the first time, being horrified by it and the hidden sexual agenda of adults, my father wanting to get me to camp presumably so he could fuck this woman while I was gone and me catching him in the act. I think this is one of the big equations why I write the novels that I write."