The first reported use of science to solve a crime happened when an ancient Greek, Archimedes of Syracuse, tested the crown his city's king had made of gold. When it was suspected this was not pure gold, a test (looking at the water displacement of the crown) showed that it was part silver. This is the story of the discovery of DNA and its applications. Inset boxes include "From Death Row Inmate to Death Penalty Activist" and "The Czar's Unusual DNA." The appendix has a two-page glossary.