Hallie Ephron's second novel, Come and Find Me, is a gently geeky melange, one part techno-thriller, two parts mystery, and three parts character study. Not a pop page-turner, this is a story that sustains the reader's interest through a soft suspense and a close focus on character. The protagonist, Diana Highsmith, is an emotionally scarred agoraphobe who has barricaded herself in her high-security house and retreated into a life online, running her software security company through an avatar on a Second Life look-alike. The disappearance of her gregarious kid sister forces her to emerge from her high-tech cocoon and begin a journey of discovery and healing. In the process, the novel touches on issues about the connections between external reality and virtual worlds, between noble ends and destructive means. But the real strength of the novel is in the ways it digs deeply into the personal world of its central character, making us care about Diana and cheer her on toward a fuller life.