Suspense fans love the thrill of the chase, so how is it possible to write a successful suspense novel when the protagonist is an agoraphobe who’s afraid to leave her home? Diana Banks, a reformed “black hat” computer hacker, hasn’t left her bunker-like house since her husband Daniel died in a mountain climbing accident. Grief-stricken and terrified of the outside world, she supports herself by working as a computer security consultant for a nationwide health care organization, and lives her “social” life online in the guise of Nadia, her computer game avatar.

Diana appears to be making the best of an unhealthy situation until her sister Ashley disappears. After being blown off by the cops, she realizes the only way to find Ashley is to overcome her terror of the outside world and search for her sister herself.

Psychologically astute and emotionally gripping, author Ephron understands that the fears we inflict upon ourselves can be more crippling than a man with a gun. She brings readers into Diana’s anguished mind so completely that no shoot-outs or car crashes are necessary for us to feel terror right along with her when she leaves her house for the first time in ages. But Diana’s love for her sister trumps her fear. Almost as gripping as the psychological suspense is Ephron’s take on the black hat versus white hat hacker wars, which reveals how their online shoot-outs can have real-life consequences for us all. A unique and compelling novel to be read more than once.