A time-travel tale in which a Maine high-school teacher goes back to try and stop the assassination of John F. Kennedy.
Well, eventually, he does that, but not until King has spent nearly 300 pages on an entirely unrelated trip to the past. It's not until 400 pages in that Lee Harvey Oswald makes his first appearance, and we're still only halfway through the book.
Lord knows King can tell an entertaining story, and this book is no exception. But he's now become so popular and famous that he's not required to submit to editing, and apparently has no interest in editing himself. The bloat here is terrible. There's some fancy technobabble at the end about the cumulative impact of all these trips to the past, but by that point, it comes off as only an attempt to justify his lazy refusal to edit.
At half the length, this could have been one of the year's best books. Not great literature, certainly, but a wonderful, breezy time travel tale. At 840 pages, it's mostly a sad example of an author who's become too big to be disciplined anymore.