A fascinating look at how scientists solve today's mysteries and centuries-old "cold cases." Savvy investigative work and scientific knowledge combine to answer perplexing questions and to uncover long-unknown truths. Using a trail of evidence - clues, careful observation, laboratories and new testing protocols - scientists reveal intriguing answers to such questions as: What really killed Beethoven? Are the Hitler diaries real or fakes? The stories and sidebars show how scientists collect clues, analyse them, test theories, and arrive at solutions - or gather enough evidence to support further investigation. The cases involve branches of science as wide-ranging as astronomy and biochemistry to geology and physics. These are gripping high-interest stories for middle-grade non-fiction lovers, with Canadian content throughout. A helpful index and glossary are also provided.