61 Hours, by Lee Child

Jack Reacher fans will be familiar with the set-up of Lee Child's 61 Hours.  Having hitched a ride on a bus tour with a group of senior citizens heading to Mount Rushmore, Reacher helps out when the bus slides off the road after hitting a patch of ice.  Reacher, along with the bus load of tourists, is stranded in a strange little South Dakotah town for a few days.  Of course, he arrives in a moment of crisis, and the town is embroiled in a major criminal enterprise.

Jack can't leave well enough alone.  The local cops quickly learn of his background as an Army investigator, and he pitches in with investigations and protective detail for a local woman who is a witness in a drug trial.  Although at first it seems simple, with a biker gang coming in and dealing meth.  But it turns out to be much larger than that, involving a Mexican drug lord and his Russian customers, a long-forgotten Air Force facility, and some corrupt locals who are under the gun.

Reacher, no surprise, gets to the bottom of it.  His kill number is actually pretty low in 61 Hours.  He only kills two, but, like all his kills, both of them totally deserved it.  One surprising element is that Child doesn't end 61 Hours with Reacher riding the bus into the sunset.  This is the only Reacher book I remember with a cliff hanger ending. . . .  As if I wasn't already eager to pick up the next book in the series.  These books are addicting.