"NCIS" is a spin-off of "JAG," which in turn spun off two more series "NCIS: Los Angeles" and "NCIS: New Orleans."
JAG is an adventure drama about an elite wing of officers trained as lawyers who investigate, prosecute and defend those accused of crimes in the military. Navy Cmdr. Harmon "Harm" Rabb, an ace pilot turned lawyer, and Marine Lt. Col. Sarah "Mac" MacKenzie, a beautiful by-the-book officer, are colleagues who hold the same high standards but find themselves clashing when they choose different routes to get to the same place. The unmistakable chemistry between them must be held at bay for professional reasons as they traverse the globe together with a single mission: to search for and discover the truth. Helping them with their mission is Navy Lt. Cmdr. Bud Roberts, a lawyer who proved his grit and determination when, after losing a leg in a land mine field while on a mission, fought back and became even better at his job.
Explore the inner workings of the government agency that investigates all crimes involving Navy and Marine Corps personnel, regardless of rank or position. Leading this team is NCIS Special Agent Leroy Jethro Gibbs, a skilled investigator and interrogator who is smart, tough and willing to bend the rules to get the job done.
NCIS: Los Angeles is a drama about the high stakes world of undercover surveillance at the Office of Special Projects (OSP), a division of NCIS that is charged with apprehending dangerous and elusive criminals that pose a threat to the nation's security, specifically Naval and Marine assets and personnel.
Jane Tennant, the first female Special Agent in Charge of NCIS Pearl Harbor, and her unwavering team of specialists balance duty to family and country while investigating high-stakes crimes involving military personnel, national security and the mysteries of the sun-drenched island paradise itself.
The eclectic team of U.S. NCIS Agents and the Australian Federal Police (AFP) are grafted into a multi-national taskforce to keep naval crimes in check in the most contested patch of ocean on the planet.
In 1991, years prior to the events of "NCIS," a young Leroy Jethro Gibbs starts his career as a newly minted special agent at the fledgling NCIS Camp Pendleton office where he forges his place on a gritty, ragtag team led by NCIS legend Mike Franks.