Where Are You Now? by Mary Higgins Clark

Clark has written 27 suspense novels and has kept up her high standards. This book is vintage Clark. Lots of red herrings in it so that you don't know whom to trust. My advice - don't trust anyone! Mack was a college senior when went missing ten years ago. All attempts to find him failed. Yet every year he calls on Mother's Day. His younger sister, Carolyn, is now twenty-six and has just finished her clerkship. She is determined to find her brother or at least find out why he has remained hidden all this time. As she begins the quest she tries to uncover all the secrets people seem to be hiding. A quick read.