In “61 Hours,” the 14th, craftiest and most highly evolved of Lee Child’s electrifying Jack Reacher books, we find out about a metal desk in a musty old office that Reacher once occupied in Virginia. “There’s a big dent on the right hand side,” says the office’s current resident, the sultry-voiced woman who holds Reacher’s old job with the military police. “People say you made it, with someone’s head.”  Reacher isn’t one to boast about that. But he doesn’t exactly deny it either. What if furniture movers made the dent?, he asks coyly. What if somebody hit the desk with a bowling ball? The woman isn’t buying that. She speaks for anyone who ever tore feverishly through a Reacher thriller and marveled at its brainy, brawny hero when she rejects any reasonable explanation for the desk’s defect. “I prefer the legend,” she says.  Who doesn’t? That legend — of a tough, cerebral drifter, a latter-day 6-foot-5-inch cowboy with “hands the size of supermarket chickens” — has been so well burnished by Mr. Child that it has now taken on a life of its own. The character is so firmly established that there are certain things Reacher can be expected to do in every story: travel light, win fights against ridiculous odds, make at least one appreciative but quick wham-bam connection with a woman and stride away when the drama is over, never to look back.  What heats “61 Hours” to the boiling point is Mr. Child’s decision to defy his own conventions. In the interests of pure gamesmanship he seems hellbent on doing everything differently this time. For starters, there’s the setting: recent books have found Reacher in assorted warm-weather American towns and in Manhattan. This one makes new rules by marooning him in South Dakota after a tour bus carrying 20 elderly tourists and one giant (“like a hitchhiker, but not quite”) skids off a road. The weather forecast calls for blizzard conditions. The wind chill will hit 50 degrees below zero. And the guy who travels through life without baggage suddenly finds himself thinking that it would be nice to have a coat.  There will be no sneaking around in a place like this. This book’s inevitable crime scenes will feature thigh-high snowdrifts, unbearable temperatures and the inevitability of leaving footprints. Those strictures, so quaint for Mr. Child, turn “61 Hours” into a closed-town mystery of the sort that Agatha Christie favored. Reacher is no Miss Marple, but he’s sure to notice that when a man claims he just arrived somewhere by car, and there’s a puddle beneath that car’s tailpipe, the man is lying.  The closed town is a burg called Bolton, and all its motels are full. That’s because Bolton is home to a brand-new correctional facility (to the north), so the place is packed with prisoners’ friends and family members. Bolton also has a cold war-era, oddly designed Army installation (to the west), purpose unknown but well worth investigating, that has since been taken over by methamphetamine-dealing bikers.  The oldsters from the bus are treated as Bolton’s houseguests. But nobody wants Reacher. He quickly becomes the local police force’s problem, tagging along with cops who are somehow too busy to pay attention to the snowstorm. He learns that they have been ordered to guard some old biddy who witnessed a drug deal, and who turns out to be another of this book’s many surprises.  Reacher finds himself oddly simpatico with the witness, Janet Salter, a solitary, bookish patrician who sizes him up and begins asking the questions that ought to have beset Mr. Child’s readers for a long time. “Your disavowal of possessions is a little extreme,” she tells him. What’s that about: phobia or philia?  She finds it strange either way. And she points out that even the most extreme ascetics manage to own clothes for more than four days at a time, unlike Reacher, who insists on regularly throwing his out and buying new ones. Other ascetics have had “shirts anyway,” Salter points out, “even if they were only made of hair.”  The title countdown in “61 Hours” is such a hackneyed device that it has no business working so well. But it does work, thanks to Mr. Child’s vigorous surge of reinvention. We are not told what kind of event is 61 hours, then 60 hours, then 59 hours away — but it will clearly involve Plato, a tiny, sadistic Mexican drug kingpin who is linked to Bolton in some dangerous way. This book’s series of tricky inversions culminates stunningly in a physical switcheroo that links Reacher and Plato, who have far more in common than either would care to admit.  Although both Plato and his nasty side can be easily dismissed as cartoonish, they make sense in this book’s overall scheme of things. Or so it seems, since this novel has a satisfying but incomplete finale. This is the first of Mr. Child’s books to end with an outright cliffhanger. Its last page offers an invitation to start counting down to Oct. 19, when the second of two 2010 books by this heretofore steady one-per-year writer will appear. Here’s hoping that Mr. Child is as smart as he continues to seem, and that the bad things that happen to thriller writers who start working too fast won’t happen to him.  No need to wait for the follow-up to find out how Reacher’s desk got its dent: that story is eventually told in “61 Hours,” after Reacher establishes an intensive phone flirtation with the throaty-sounding woman who holds his old job as an officer with the military police. They make contact because Reacher needs her help in finding out what went on at Bolton’s mysterious old government installation. (“How hard will you dig?” he asks. “As hard as you want me to,” she answers.) And they bond, though not in the way readers of Mr. Child’s 13 other books will expect.  A head did hit the desk. The whack was Reacher’s doing. But Reacher had what, for him, was a good reason. And the woman made the wrong choice by preferring the legend. The truth about Reacher gets better and better.
Lee Childâs tough, cerebral hero Jack Reacher returns in a thriller that finds him snowbound in South Dakota.