NCIS season 18 is currently in production. A lot of stories are coming in the latest installment once it arrives in the fall on CBS. But, the premiere will mostly focus on the past rather than the present. It will explore more on Gibbs' (Mark Harmon) previous mission.

In a new interview with TVLine, co-showrunner Steven D. Binder confirmed that NCIS season 18 will pick up where Gibbs was in season 17 episode 8, titled "Musical Chairs." He took off from the squad room to do a secret, personal mission; something that will be addressed in the early run of the new season.

Binder said that the upcoming installment picks up the events in that particular mission Gibbs was working on, which means the story goes back in time. He made it clear that the premiere will be a "pre-pandemic" world for a little while.

This is an interesting move for the series, given that some past stories weren't given proper closures. This is a chance to dive back in other storylines, including the opioid ring, which was first brought up in the season 16 finale, titled "Daughters." This story wasn't really addressed in season 17.

And since the early run of NCIS season 18 will focus on the storylines in the past, there's a possibility that other relationships won't be immediately explored. When all of these were wrapped up properly, the story could move forward to the present timeline.

The new season could deliver stories about the global health crisis, as well. We could see most of the characters dealing with the current situation while working on the field. It would be challenging for them to go on a mission amidst the pandemic.

Meanwhile, the 400th episode is part of NCIS season 18. It will focus more on Gibbs and Ducky's (David MacCallum) early years. The story features their younger years, including how Gibbs came into the NCIS world and how he first met the met medical examiner and now historian, Ducky.

Back in June, executive producer Frank Cardea told TV Insider that the goal of the 400th episode was meant to write a "love letter" to the longtime fans. It's interesting to see the things they've been through before. However, it's yet to be seen whether it will be addressed in the actual past or through flashbacks.

The official release date of NCIS season 18 wasn't revealed at the moment. But, the upcoming installment is slated to premiere in November.