Explore the complexities of serious crime investigations in this expert talk by Dr. Robert Green OBE. Delve into the challenges of conducting criminal investigations in unpredictable situations with limited information. Learn about crucial concepts, legal regulations, and processes that must be adhered to in every investigation. Gain insights into cold case resurrection, advancements in forensic science, and the evolution of investigative techniques. Discover how 215 cases were handled, the tracking process, and the impact of scientific progress on solving crimes. Examine specific cases, including those involving sexual deviants and prolific unknown offenders. Understand the concept of double jeopardy and its implications in criminal investigations. Conclude with key takeaway messages from Dr. Green's extensive experience in the field of forensic science and criminal investigation.