Where Is Mark Harmon's Gibbs? NCIS Season 21's Ducky Episode Confirms His Current Location

"NCIS" Season 21's second episode is quite a significant installment. Not only does the episode pay tribute to the late series star David McCallum and his character of Dr. Donald "Ducky" Mallard, but it also serves as something of a trip down memory lane for the series. In particular, the episode revisits classic moments and provides updates on a couple of old characters. In fact, fans have obtained a notable update on Mark Harmon's Leroy Jethro Gibbs and where exactly the character has been since his exit from the series in Season 19.

While Harmon's Gibbs doesn't actually make a physical return in Season 21, Episode 2, titled "The Stories We Leave Behind," his presence is still felt by way of a letter that he sends to Sean Murray's Timothy McGee. Partway through the episode, McGee opens the envelope to find a Polaroid of himself, Gibbs, and Ducky all together — a memento clearly sent by Gibbs to honor his late friend. But while it's a nice, sentimental moment, this scene also provides an update on Gibbs' whereabouts.

McGee's letter has a return address for the fictional town of Naktok Bay, Alaska — the very same place that Gibbs flees the country to during a complicated case in Season 19, Episode 4, titled "Great Wide Open." In that episode, Gibbs develops an attachment to the locale and elects to stay when the case is ultimately resolved. Per the update in Season 21, the former agent is still there, presumably enjoying his retirement.

Prior to the release of "NCIS" Season 21's Ducky tribute episode, many fans speculated that Mark Harmon's Gibbs would return for his ex-teammate's funeral. After all, the pair forge a strong friendship over the course of their shared time on the series and it follows that Gibbs would turn out to pay his respects to his old friend. However, despite "NCIS" bringing back a huge original character for the episode in the form of Michael Weatherly's Anthony "Tony" DiNozzo, Gibbs' letter to McGee is the extent of his involvement. While little explanation is given for Gibbs' physical absence, it seems that the real reason possibly stems from actor availability and scheduling conflicts.

Though Harmon wasn't specifically mentioned, "NCIS" star Brian Dietzen, who co-wrote the tribute episode, noted to TV Insider that the team considered bringing other characters besides DiNozzo back, as well. However, as he explained in a separate interview with TVLine, they could only accomplish so much. "Can we get every person that's ever been in the history of 'NCIS,' and all of its sister shows, back together for one scene where everyone's sitting together? Logistically, those things aren't really a possibility, unfortunately," he said.

Ultimately, the team decided to incorporate references to other characters in the episode, such as Gibbs' letter. "We tried to have shout-outs to these other field offices around the country, throughout the show, and also show tokens of admiration and honor that are coming from past team members — as well through flashback scenes, or even gifts that they're sending, tokens of love," Dietzen said.