Gil Grissom is a fictional character from the television series CSI: Crime Scene Investigation. He serves as the supervisor of the Las Vegas crime lab and is known for his analytical mind and deep understanding of forensic science. Grissom often relies on evidence and scientific methods to solve complex cases, showcasing his dedication to justice. Portrayed by actor William Petersen, Grissom is characterized by his calm demeanor and passion for entomology, the study of insects. His unique approach to investigations often involves examining the smallest details, which helps him uncover crucial information that others might overlook.