CSI or Crime Scene Investigation is becoming one of the longest TV series in the US. It started with CSI Las Vegas with William Petersen acting as Gil Grissom as the head of the crime scene unit. They’ve had successful runs as they’re in their 9th season. They’ve lost two of their original crew and have a new CSI this season. In the beginning, it was a must watch but after 8 seasons some of their plots seem to be recurring and their appeal seems to be dwindling. Also, I think you’ve seen the whole of Las Vegas from watching all their episodes.