On a spring morning in 1979, 6-year-old Etan Patz left his Manhattan apartment to walk to the school bus stop for the first time — and vanished forever. His disappearance sparked an exhaustive search and a national movement to protect missing children, leading to hotlines, new laws, and a legacy that still shapes how the United States responds to missing kids. Decades later, the legal battle continues, with a man once convicted now awaiting a new trial as questions linger about what really happened that day.