“The Nanny kept me in white-knuckled suspense until the very last page. Gilly Macmillan’s breakout thriller is a dark and twisted version of Downton Abbey gone very, very wrong.” — Tess Gerritsen,  New York Times bestselling authorThe New York Times bestselling author of What She Knew conjures a dark and unpredictable tale of family secrets that explores the lengths people will go to hurt one another.When her beloved nanny, Hannah, left without a trace in the summer of 1988,