10 Spin-off TV Shows That Made It Big

Though it has inspired a number of series of its own, "NCIS" actually got its start as a spinoff of "JAG." CBS Photo Archive/Getty Images

Is it fair? In 2003, "NCIS" was created from "JAG," a series that had a long, successful run. The CBS spin-off, however, went on to eclipse that accomplishment. Though "JAG" ran from 1995 to 2005, "NCIS" is still going strong in the mid-2010s. In fact, according to CBS, "NCIS" had the audacity to be the most-watched American show for five years in a row. To add insult to injury, in 2013, it was ranked No. 1 in the world.

What makes this series about the Naval Criminal Investigate Service so watchable? An intriguing mix of professionals investigates alarming and sometimes odd criminal activities. The diverse team includes a former homicide detective, a Marine gunnery sergeant, a scientist with Gothic flair, and an MIT-educated computer specialist. Need to foil a terrorist plot? They're on it. Stolen submarine? Call in the squad. An intelligence leak? Have no fear – The Navy and Marine Corps have never been so safe. "NCIS" has gone on to spin off its own franchisees "NCIS: New Orleans" and "NCIS: Los Angeles."