Gone Unknown - 2006

From the publisher

From "New York Times" bestseller Lisa Gardner, author of Alone and The Killing Hour," "comes a thriller that goes from heartbreaking to heartstopping in the blink of an eye....
"When someone you love vanishes without a trace, how far would you go to get them back? "For ex-FBI profiler Pierce Quincy, it's the beginning of his worst nightmare: a car abandoned on a desolate stretch of Oregon highway, engine running, purse on the driver's seat. And his estranged wife, Rainie Conner," gone, "leaving no clue to her fate.
Did one of the ghosts from Rainie's troubled past finally catch up with her? Or could her disappearance be the result of one of the cases they'd been working-a particularly vicious double homicide or the possible abuse of a deeply disturbed child Rainie took too close to heart? Together with his daughter, FBI agent Kimberly Quincy, Pierce is battling the local authorities, racing against time, and frantically searching for answers to all the questions he's been afraid to ask. One man knows what happened that night. Adopting the alias of a killer caught eighty years before, he has already contacted the press. His terms are clear: he wants money, he wants power, he wants celebrity. And if he doesn't get what he wants, Rainie will be gone for good.
"Sometimes, no matter how much you love someone, it's still not enough."As the clock winds down on a terrifying deadline, Pierce plunges headlong into the most desperate hunt of his life, into the shattering search for a killer, a lethal truth, and for the love of his life, who may forever be...gone.