The Stranger by Harlan Coben

You go about your life, following your normal routines, seeing the same people and doing the same things.  It's a nice life, maybe not thrilling or breath-taking, but comfortable and enjoyable.  Then he appears.  The Stranger.  He sidles up to you, maybe in a store, a restaurant or a parking lot.  He talks for a few minutes and when he stops, your world has exploded and things will never be the same again.

That's what happened to Adam.  The Stranger comes up to him and tells him a secret about his wife, Corrine.  A secret that she'd never want him to know about.  A secret he doesn't know if he can forgive.  When he confronts Corrine, she refuses to discuss it and disappears, the only clue a text message saying she needs some time apart.

There are others who gets a visit from the Stranger also.  Maybe a high school senior with a big scholarship who cheated on a test.  Maybe a man whose marriage is a lie and is only there as a smokescreen to hide his true sexuality.  Maybe a parent whose child has done something horrendous that surely they never meant to do.  Regardless, he tells the secrets and then walks away.

Harlan Coben has created a situation that is both unimaginable and yet easy to believe in.  Adam is thrust into the role of a detective as he tries to find the Stranger and discover where Corrine has gone.  The reader feels the tension as clue after clue is revealed, and the number of lives that are touched by the Stranger's game mount up.  This book is recommended for mystery readers.