Leroy Jethro Gibbs is the special agent in charge on NCIS.

Gibbs joined the United States Marine Corps instead of attending college. He became a Scout Sniper.

In his free time, he is occasionally shown in his basement building a boat, which he named after his daughter.

Gibbs' age has never been revealed, but it was shown that he was born in rural Stillwater, Pennsylvania. His father, Jackson Gibbs, owns a store (the Stillwater General Store) in the same town.

It has been mentioned in the episode "Frame Up" that Gibbs' father was possibly in the United States Army Air Force because Gibbs refers to a pin-up on his father's P-51 Mustang.

He is named after his father's friend, Leroy Jethro, who was his business partner in the store after having worked together in the coal mines. The younger Gibbs left Stillwater in 1976 at the approximate age of 18-20 and, according to his own statements, did not return for over 30 years.

At NCIS, Gibbs is portrayed as a consummate organizer, disciplined and demanding. These traits often put him in a stand-off with other authorities when pressure is being asserted at his team.

He remains a Marine reservist.

Before the time in which NCIS is set, Gibbs travelled extensively on operations, particularly in Eastern Europe, demonstrated by many flashbacks, many including Director Jenny Shepard.

Gibbs displays a continuous urgency about the investigation he pursues, specifically when being given technical information about, complex subject matter.

The typical response to such information is "Give it to me in English", thus forcing the expert to get to the point, as well as making it easy on the audience.

Gibbs has been married three times and had one daughter named Kelly.

Leroy Jethro Gibbs Quotes

Bishop: All we know for sure is that he went to college with Amanda Kendall. His murder could be a coincidence.
Gibbs: McGee.
McGee: Rule 39, Bishop.
Bishop: Right. No such thing as a coincidence. I knew that one.

Man up, Marine!

Gibbs

NCIS Quotes

Abby: Have the bad things been outweighing the good things all these years and I just ever noticed?
McGee: What do you mean?
Abby: All I ever wanted was to help people with the truth. And I've done that, but then bad still won sometimes. And I just want to file it away, like it never happened so I can go back to being happy.
McGee: There's nothing wrong with that.
Abby: Yes there is McGee because sometimes the Cutwrights and the Dunns, they just keep fighting no matter what the truth is. And sometimes Ricki never gets to see her grandpa again. If the bad outweighs the good then that means that I'm not enough.
McGee: Abby listen to me...
Abby: And if I'm not enough, McGee, then why even try?

Abby: It's okay. Breena's fine. Breathe. Good. Now hurry up and get to the hospital because Breena is in labor.
McGee: Jimmy? Did you hear what she said? She just said Breena's having a baby. I think you broke him.