David Berkowitz, known as Son of Sam and the.44 Caliber Killer, was born Richard David Falco on June 1, 1953. His mother, Betty Falco, a factory worker, chorus girl, and store owner, was separated for many years from her husband, during which time she maintained a relationship with Berkowitz's biological father, a married man named Joseph Klein. When he discovered she was pregnant, Klein insisted the baby be given up for adoption. When he was only a few days old, Berkowitz was adopted by Nathan and Pearl Berkowitz, a Jewish couple from the Bronx. Though of average intelligence and a B student, David was a solitary child. He was overweight and extremely shy (especially with girls).

Three events were important in Berkowitz's childhood. First, at age 3, his parents told him he was adopted. But in doing so they fabricated the lie that his mother had died in childbirth. The Berkowitzes...