CSI: Crime Scene Investigation ranked number 1 in Nielsen’s season-three television ranking for the 2002–03 U.S. broadcast season. It averaged about 26.12 million viewers per episode, making it the country’s most-watched program that season.
The ranking marked a major rise for the CBS crime drama. CSI had placed 10th in its first season, then climbed to 2nd in season two before taking the top spot in season three. Its combination of forensic science, procedural storytelling, and a strong Thursday-night time slot helped turn it into television’s defining crime franchise.
The number can be confused with a Nielsen rating, which is a separate measurement from a program’s rank. CSI’s season-three position means it finished ahead of every other listed prime-time series by average audience, not that it received a rating of exactly 1. The show remained among television’s biggest hits for several more seasons.