Stephen King opens his novel “11/22/63” ― billed as an alternate universe reimagining of the John F. Kennedy assassination ― with an epigraph from Norman Mailer’s “Oswald’s Tale.” “It is virtually not assimilable to our reason that a small lonely man felled a giant in the midst of his limousines, his legions, his throng, and his security,” Mailer writes. “If such a non-entity destroyed the leader of the most powerful nation on earth, then a world of disproportion engulfs us, and we live in a universe that is absurd.”

There it is, the ultimate underpinning of every Kennedy conspiracy ever invented, the idea that Lee Harvey Oswald was not a worthy foil. I’ve gone back and forth on this myself for nearly 40 years: Did Oswald act alone or was he a patsy, as he protested on the night of the assassination in the custody of the Dallas police? Was he part of a conspiracy or a twisted figure intent on blasting his way into the history books?

For a long time, I thought it was the former, but now I’m not so sure. If at the heart of all conspiracy theories is the notion that the universe makes sense (a version, in its way, of the belief in God), then I’ve come to think more often that the universe is a manifestation of chaos, in which things happen for no reason or for no reason we can see. What seems more probable ― that Kennedy was the victim of a conspiracy or that he was taken out by a loser with a mail-order rifle and a grudge against the world?

These are parlor game questions, but at their center resides a curious belief in logic, or order, another form of the conspiracist’s faith. There must be meaning to the story, such a belief insists, when, in fact, it’s just as likely that there wasn’t any.

Such issues motivate “11/22/63,” which deals with a man named Jake Epping, who goes back in time to derail Kennedy’s date with death. To make the story work, after all, King has to come down firmly on one side or the other; it’s impossible to stop a crime if you don’t know who your target is. “There was no way of knowing anything for sure,” Jake acknowledges, although the twist of the book is that he knows almost everything, coming from the future as he does. For him, then (and, by extension, for us), much of the narrative takes the form of an elaborate waiting game, as Jake stalks Oswald, trying to make sure there are no conspirators, while also desperate not to be seen.

“He’s going to notice me and he’s going to speak to me,” Jake thinks, when he comes close to encountering his quarry on a Dallas street. “He’s going to say, ‘Aren’t you the guy who lives downstairs? What are you doing here?’ If he did, the future would skew off in a new direction. Not good.”

This is the conundrum of any time travel story ― what King invokes as the butterfly effect. Every action taken in the past has an effect on the future, which means even the best intentions often have unintended consequences. Jake discovers that early in the novel, when he tries to save a man he knows from a childhood catastrophe, only to learn, upon returning to the present, that in the new world he’s created, his acquaintance was killed in Vietnam.

Fortunately, the past resets each time he visits it, which means Jake can make things right simply by taking another journey in time. And yet, if this allows Jake a shot at redemption, it also undermines the tension of the book. The larger point may be that time is always fluid, but by building a do-over button into his narrative, King makes everything conditional, to the point where nothing really matters all that much.

Part of the problem is the conceit of the story, which requires Jake to spend years in the past to effect the change he has in mind. The wormhole he’s discovered sends him to September 1958, five years before the assassination; he then needs to live in that lost landscape ― the world of Ago, as King puts it ― as he bides his time. This is one reason the novel is so long (too long by half, I’d suggest), but even more, it’s why it doesn’t hang together in a cohesive way.

Instead, “11/22/63” reads like two books welded together: the first a follow-up to King’s 1986 bestseller “It,” set in the fictional Maine town of Derry and complete with references to that novel’s string of child murders and cameos by Richie Tozier and Beverly Marsh, and the second an assassination rhapsody. It takes nearly 300 pages for us to get to Texas, and once we’re there, 400 more before the drama peaks. Along the way, there are nice bits of domestic detail as Jake settles down and falls in love with a woman who makes him question his sense of time and belonging. There are loose reflections on the space-time continuum, which Jake is always aware of having disrupted, for better or for worse. And then there is Oswald, who Jake determines, to the best of his ability, really is a lone gunman: bitter, derisive, a closet wife-beater, caught between the tawdriness of his real life on the margins and the grandiosity of his fantasies.

This is, or should have been, the meat of “11/22/63,” and, indeed, when we see Oswald, the book achieves a gritty urgency. Why? Because half a century after the assassination, Oswald remains an empty vessel, a template for our dystopian dreams. Over the years, more than one writer has zeroed in on him ― Mailer as well as Edward Jay Epstein, whose “Legend: The Secret World of Lee Harvey Oswald” looks at his ties to the intelligence community, and Don DeLillo, who portrays him as a cipher in his 1988 novel “Libra.”

And yet in the end, “11/22/63” falls short of these investigations for it is not Oswald’s tale but Jake’s, the story not of an agent of chaos but of someone who sought to set the universe right. That this is impossible only goes without saying: It’s that time-travel conundrum once again. Still, for all King’s rhetoric about time and history, Jake never fully gets it: That the universe is implacable, that things happen for no apparent reason, and that order, logic and intention, the elusive grails that drive this novel, can become their own sort of conspiracy theory, a faith in meaning that experience belies.

By David L. Ulin

(Los Angeles Times)

(MCT Information Services)