THE SUNDAY TIMES NUMBER ONE BESTSELLER Be careful before answering your next call. It could be the beginning of your worst nightmare. After a tough week, Tanya Kaitlin is looking forward to a relaxing night in, but as she steps out of her shower, she hears her phone ring.  The video call request comes from her best friend, Karen Ward.  Tanya takes the call and the nightmare begins.     Detectives Robert Hunter and Carlos Garcia are thrown into a rollercoaster of evil, chasing a predator who scouts the streets and social media networks for victims, taunting them with secret messages and feeding on their fear.  AS ADDICTIVE AS A TV BOXSET! PRAISE FOR CHRIS CARTER  'Carter has a background in criminal psychology and the killers at the centre of his novels are all the more terrifying for it' Mail on Sunday, chosen for 'If You Only Pack One' 'Carter is one of those authors who makes writing look effortless . . . I couldn't put it down' Crimesquad 'An insanely good crime seri