Beware the Man of the Year. You may praise him, resent him, even want to be him: but beneath the elegant trappings that define him, danger looms. Caroline Louise Walker’s stunning debut novel, for fans of Herman Koch’s The Dinner and Shari Lapena’s The Couple Next Door, delves into the increasingly paranoid mind of a man whose life as the most upstanding of citizens hides a relentlessly dark heart. Dr. Robert Hart, Sag Harbor’s just-named Man of the Year, is the envy of his friends and neighbors. His medical practice is thriving.