This true crime book makes you the detective, investigating some of the most infamous unsolved cases of the 20th and 21st centuries. MURDERS THAT DEFY DETECTION. Discover the stories behind some of the most infamous unsolved murders of the last century, including the Black Dahlia, the Zodiac Killer and the JonBenét Ramsey case. Detailing essential evidence.Profiling key suspects.Tracking police investigations. Sorting facts from speculation.