The characters Leroy Gibbs (Mark Harmon) and Leon Vance (Rocky Carroll) have long been staples of “NCIS.” Gibbs has been with the show since the very beginning, whereas Leon entered the picture in Season 5. On the “NCIS” subreddit, fan OkGuitar3773 brought up the complicated dynamic between these two characters, writing, “I’ve heard people say Gibbs didn’t like Leon because he split up the team. But before that ever happened there was already tension with them.” The user went on to defend Leon, claiming that the character gets too much “unwarranted” hate, and suggesting that it isn’t technically “his job” to keep Gibbs informed on everything. Lastly, OkGuitar3773 points out that both the characters are guilty of keeping secrets from one another.
User Siobhan945 theorized that the reason the two characters are at odds is because they both have their superiors, and sometimes their orders seem to conflict. User HugeRaspberry noted that their relationship is surely a complicated one but the tension between the two seemed to ease out when Leon was in the hospital. Regardless it definitely seems like the relationship between Gibbs and Leon has brought almost as much discussion as the show’s central mysteries.