NCIS, formerly known as NCIS: Naval Criminal Investigative Service, is an American police procedural drama television series revolving around a fictional team of special agents from the Naval Criminal Investigative Service, which conducts criminal investigations involving the U.S. Navy and Marine Corps.

The concept and characters were initially introduced in a two-part episode of the CBS series JAG (JAG episodes 8.20 and 8.21). The show, a spin-off from JAG, premiered on September 23, 2003 on CBS and, to date, has aired nine full seasons and has gone into syndicated reruns on USA Network, Cloo (formerly Sleuth), and Ion Television. Donald Bellisario, who created JAG as well as the well-known series Airwolf, Magnum, P.I., and Quantum Leap, is co-creator and executive producer of NCIS.

NCIS was originally referred to as Navy NCIS during season one; however, the word "Navy" was later dropped from the title as it was redundant. In season seven, NCIS was joined by a spin-off series, NCIS: Los Angeles, starring Chris O'Donnell and LL Cool J.

María José de Pablo Fernández, better known as Coté de Pablo (born November 12, 1979), is a Chilean-American actress and recording artist. She is best known for her role as Ziva David in the CBS television series NCIS, for which she has won an ALMA Award. She has also embarked on a career as a songwriter and vocalist.

De Pablo was born in Santiago, Chile, to an upper-classCatholic family. She has a younger sister, Andrea, and a brother who works as a DJ. In the 5th grade, she found many people could not properly pronounce her first name of "Maria José" so she asked them to call her Coté (a common Chilean nickname for María José). When de Pablo was 10 years old, her mother, María Olga Fernández, received a job in Miami, Florida, at a Spanish-speaking television network. There, de Pablo attended Arvida Middle School and New World School of the Arts where she studied musical theater. She then attended Carnegie Mellon University in Pittsburgh, Pennsylvania, where she studied music and theater and appeared in several plays. These aforementioned plays include: And The World Goes 'Round, The House of Bernarda Alba, Indiscretions, The Fantasticks, and A Little Night Music. She graduated in 2000.

Michael Manning Weatherly, Jr. (born July 8, 1968) is an American actor, best known for his roles as Special Agent Anthony DiNozzo on the television series NCIS, and Logan Cale on the television series Dark Angel.

Michael Weatherly was born in New York City on July 8, 1968, and raised in Fairfield, Connecticut, by parents Patricia O'Hara, a hospital administrator, and Michael Manning Weatherly, Sr. He graduated from Brooks School in North Andover, Massachusetts, in 1986. Subsequently, he spent some time at the American University of Paris but he left college to pursue acting. He also had a great passion for music, and played in a band while pursuing his acting career. Despite not continuing this, he contributed the song Bitter and Blue to the second soundtrack album of NCIS.

Weatherly began his professional acting career with a minor television role on The Cosby Show as Theo Huxtable's roommate.

He then obtained the role of Cooper Alden on Loving and later, The City, which he would portray from 1992 until 1996.

Mark Harmon (born September 2, 1951) is an American actor. Since the mid 1970s, he has appeared in a variety of television, film and stage roles following a brief career as a collegiate football player with the UCLA Bruins. Since 2003, Harmon has starred as Leroy Jethro Gibbs in the hit CBS series NCIS.

Harmon was born Thomas Mark Harmon in Burbank, California. His father was University of Michigan football All-American and Heisman Trophy winner, Tom Harmon. His mother was actress and artist, Elyse Knox (née Elsie Lillian Kornbrath). Harmon has two older sisters, actress and painter Kristin Nelson, the former wife of singer Ricky Nelson, and actress-model Kelly Harmon, who was once married to car magnate John DeLorean.

After attending Los Angeles Pierce College as a student and quarterback, Harmon transferred to the University of California, Los Angeles, and following in his father's athletic footsteps was the starting quarterback for the UCLA Bruins football team in 1972 and 1973. In UCLA's 1972 season he engineered a stunning upset of the two-time defending national champion, Nebraska Cornhuskers. He received the National Football Foundation Award for All-Round Excellence in 1973. In his two years as quarterback in coach Pepper Rodgers' wishbone offense, UCLA won 17 games and lost only 5. He graduated from UCLA with a B.A. in Communication cum laude in 1974.

Roscoe "Rocky" Carroll (born July 8, 1963) is an American actor. He is known for his roles as Joey Emerson on the FOX comedy-drama Roc, as Dr. Keith Wilkes on the medical drama Chicago Hope, and as Leon Vance on the CBS drama NCIS and its spinoff NCIS: Los Angeles.

Carroll was born Roscoe Fulton Carroll in Cincinnati, Ohio. His acting career is rooted in the theater. In 1981, Carroll graduated from the famed School for Creative and Performing Arts. Determined to further his knowledge of acting, he attended The Conservatory of Theatre Arts at Webster University in St. Louis, where he graduated with a B.F.A. degree. After graduating, Carroll decided to test the waters by moving to New York City, the heart of the theater community. There, he introduced many young children of color to the works of William Shakespeare by participating in Joe Papp's “Shakespeare on Broadway” series.

Carroll married Gabrielle Bullock on May 25, 1996. They have one daughter, Elissa.

As part of Joe Papp's acclaimed New York Shakespeare Festival, Carroll helped to open doors for actors of color, by taking on non-traditional roles that were rarely portrayed by Black actors in Shakespeare dramas. In 1987, Carroll was introduced to the works of August Wilson. The up and coming and talented young actor was allowed to recreate his role for the Broadway production of Wilson's critically acclaimed story The Piano Lesson. The play not only earned a Pulitzer Prize for Drama, but Carroll earned a Tony and Drama Desk nomination.