IF YOU THINK YOU'RE ALONE:THINK AGAIN A scratching at the window.A tap on the door.What if, this time, someone is out there? A silent killer stalks the city, targeting those home alone at night, playing a deadly game of cat and mouse with the victims.As panic spreads, Detective Inspector Helen Grace leads the investigation, but is herself a hunted woman, her every step shadowed by a ruthless psychopath bent on revenge.As she tracks the murderer, Grace begins to suspect there is a truly shocking home truth that connects these brutal crimes. But what she will find is something more twisted than she could ever suspect...*****PRAISE FOR THE MILLION-COPY BESTSELLER M. J. ARLIDGE:'Chilling' THE TIMES'Addictive'EXPRESS'Truly excellent' THE SUN'Amazing' RICHARD MADELEY'Terrifying and wildly compelling ... Nobody does chilling suspense quite like M.J. Arlidge'B.P. WALTER'Helen Grace is one of the greatest heroes to come along in years'JEFFERY DEAVER'Mesmerizing' LISA GARDNER'Chills to the bone' DAILY MAIL