5. Gil Grissom
William Petersen portrays Gil Grissom, Ph.D. in the Crime Scene Investigation (C.S.I.) series. Grissom is the night shift supervisor of the forensics team in Clark County, Nevada as well as a forensic entomologist. Grissom and his team investigate crimes that take place in Las Vegas and the areas surrounding it.
Grissom is relentless in his search for logic to conquer a problem. In the early seasons Grissom was flirty, enthusiastic and had a sense of humor. After he started to lose his ability to hear he became less approachable. However, he did become more like his old self after having surgery, but he never fully regained his quirky personality.
After some years Grissom took a sabbatical to teach at a college in Massachusetts for about a month. Still later in the series Grissom retired and only made occasional appearances in several episodes. Grissom appeared regularly in the first eight years of the series. Critics gave positive reviews for Grissom and AOL named him one of TVs Smartest Detectives.