From the #1 New York Times bestselling author of Hidden Valley Road comes the heart-wrenching journey of a family facing an unthinkable destiny, whose flawed genetic code might hold the long-sought key to a cure for dementia.

In the idyllic American town of Pleasant Hills, Pennsylvania, there lived a family with nine siblings, the youngest a girl named Barb. As the older children headed off to college and started their lives, only Barb was home to see their beautiful, still-young mother fall under a gothic spell, changing into someone she didn’t recognize: withdrawn, neglectful, uncaring. Thus begins The Vanishing Family, journalist Robert Kolker’s superb follow-up to Hidden Valley Road (“Deeply compassionate and chilling,” wrote The Washington Post). This family, we learn, has a genetic mutation that causes dementia, but with an especially cruel twist. As early as their forties, formerly loving parents and hard-driving executives will lose their jobs, have affairs, take up drinking—shed all inhibitions and sense of responsibility—and become people their families hardly know. Their former personalities seem to vanish—and there is a fifty-fifty chance that it will happen to their children, too.

The Vanishing Family unfolds like a heartbreaking thriller as the siblings begin to realize that what happened to their mother is happening to them: first one, then two, three, four, and more begin to change. Sue, in search of a calling, finds her place in caring for the others. Barb sets out to find a cure. Alongside their story, Kolker weaves in the dramatic scientific fight against dementia; after decades of blind alleys, this this family’s rare form of FTD (frontotemporal dementia) might lead to a breakthrough in the prevention and treatment of all dementia—including the scourge of Alzheimer’s disease. Moving, intimate, unexpectedly hopeful and redemptive, The Vanishing Family is an enthralling narrative about one family’s fate, and a medical detective story that speaks to all of us who fear losing ourselves at the end.