In its 18th season, the popular crime procedural NCIS will reach a milestone when the 400th episode airs this fall. TVInsider reports that viewers will be taken back to the start of a very important relationship of "Special Agent Leroy Jethro Gibbs" (Mark Harmon, 68). Also, an old case from a few years back will be reopened.

NCIS: "Gibbs", "Ducky" and "Jack"

What many fans are still waiting for is a happy ending for "Gibbs" when it comes to his romantic relationships. Even though there is a spark between him and "Jack Sloane" (Maria Bello, 53), NCIS executive Producer Frank Cardea "said that Gibbs needs to go through a bit of personal growth first," according to Cinemablend.

But that does not mean that there is no chance at all for some romance on NCIS in season 18, but we will have to wait a little bit until that happens. The opportunity to work on himself will definitely come for "Gibbs" later on in the new season.

RELATED: This Hollywood Icon Almost Played The Part of "Gibbs" On NCIS!

NCIS: More details on season 18

According to TVInsiderthe 400th episode, will reveal to fans how "Gibbs" first came into the NCIS world and how he met his long-time colleague "Ducky Mallard" (David McCallum, 86). And another story involving "Gibbs" will also be wrapped up.

In season 16 of NCIS, Agent "Fornell's" (Joe Spano) daughter "Emily" nearly died of a fake opioid overdose. The Canadian dealer couldn't be caught at the time, but there is apparently evidence that "Gibbs" is still on the case, which will be reopened in season 18 according to TVInsider.

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