Spoiler Alert: This article contains spoilers for Season 19, Episode 1 of NCIS.\n\nEver since it was announced that Mark Harmon would be taking a step back from NCIS, fans have been clamoring to find out what this means for his character, Leroy Jethro Gibbs. To quote The Clash, "Will he stay, or will he go?" And furthermore, is FBI Special Agent Alden Park, played by Gary Cole, gearing up to be his replacement?What is the current status of Gibbs on 'NCIS'?Is it any wonder fans of the show are so stressed out? By the end of last season, we'd lost two series regulars: Maria Bello's Jack Sloane and Emily Wickersham's Ellie Bishop. And if that's not enough, after living through a boat explosion, Gibbs survives only to end up locked inside a barn by a wacky couple who mistakenly believe he is part of a gang giving them trouble.Coming out of a major explosion unscathed is impossible. Gibbs has a chunk of the boat lodged in his side, but as luck would have it, the husband of the aforementioned sassy couple is a veterinarian. If you've stitched one kind of flesh, I guess you can stitch any kind of flesh. Of course, the team doesn't give up on finding him, with a little help from a tracking device in the electronic bug-finder Kasie lent to Gibbs. Eventually, the team is restored and all is right with the world. Or is it?What do we know about Special Agent Alden Park on 'NCIS'?So far, the only thing we know for sure is Special Agent Alden Park is a member of the FBI. The mystery surrounding him is fueling many fan theories. The leading theory is that Agent Park, played by Gary Cole, is the serial killer. In fact, all of Season 19 is being held together by the promise of finally figuring out who the killer is.Is Park replacing Gibbs on 'NCIS'?Mark Harmon was ready to leave the show until he found out that his exit would lead to its cancellation. Taking a step back is hardly tantamount to quitting. Clearly, some changes are in the air, the biggest one being the show's new time slot. “We hope to improve the [Monday] time period significantly, and we hope that it can be a strong lead-in to help launch NCIS: Hawai’i," said CBS Entertainment President Kelly Kahl to TV Line.According to TV Line's sources, fans need not worry that acting veteran Gary Cole is coming for Mark Harmon's job. We'll likely have to wait and see just what Gary will be doing on the show instead.Gary already has a very impressive resume. From his voiceover work in Family Guy as Principal Shepherd to his time on award-winning shows like The West Wing and Veep, he is a natural fit for NCIS. And who could forget his role as the boss in Office Space with those darn TPS reports. NCIS showrunner Steven D. Binder had this to say about Season 19: “We are excited to have new characters and stories to tell that adds to and re-energizes the world we’ve come to love over the 400-plus episodes.”Catch NCIS Mondays at 9 p.m. EST on CBS.