Claire Sturgis never dreamed of leaving her life as a Washington, D.C. urbanite. But after her husband, Sam, a NASA aerospace engineer working on a top-secret project, is diagnosed with early-onset dementia, he convinces her semi-retirement in a gated community full of "McMansions" is just what they need to slow down and take stock. She silently begrudges the move, but will do anything to help him deal with his illness. But as soon as they arrive at Frontier Village, Claire finds more questions than answers. Why is their rural neighborhood surrounded by a 15-foot-high wall festooned with high-tech video cameras? Why are there no children? And why is the couple who live down the street so perfect and beguiling? When Sam insists that they're being followed home from dinner one night, Claire must decide whether to believe him, or accept the fact his disease is finally taking hold. Soon it's not just Sam who is losing his grasp on reality, as Claire struggles to uncover the truth about her overly-friendly neighbors, her husband and, ultimately, herself.