Natalie Rubin, middle-class Jewish wife and mother, has vanished. Worse, she has taken her three children with her. Her husband, Mark, is devastated. He loves her; and he thought she was happy. So he approaches Tess to trace her. At first Tess is wary. She doesn't like getting involved in domestic disputes, and Mark's love for his wife seems to contain a disturbing desire to control her. Did he drive her away? Did he perhaps kill her? But as Tess pursues her quest for Natalie, she discovers a woman with a mysterious past, a man whose values will challenge her own, and a family that knows how to keep its secrets ... BY A SPIDER'S THREAD is part tense thriller and part all-too-human drama about what families do to each other.