He is one of the longest-serving American TV stars, so it's no surprise that the news that Mark Harmon has finally bowed out of hit police procedural NCIS has left fans aghast.
On Monday night's episode, the actor ended his 18-year run as the CBS drama's lead, with his character, Special Agent Leroy Jethro Gibbs, deciding to retire from law enforcement.
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While viewers were relieved that the character hadn't been killed off after all, many were left completely devastated by the surprise announcement nonetheless. Taking to Twitter to discuss after the credits rolled, one upset fan wrote: "You broke my heart completely @NCIS_CBS. NCIS will never be the same without Gibbs."
Another echoed this, tweeting: "I don't think you understand just how much I'm SOBBING right now! Gibbs has made an impact on so many people, and it shatters my heart to see him go."
However, a third added: "I'm gonna miss Gibbs too but you got to realize Mark has been doing NCIS 18 or 19 years and he's 70. He's getting old, he probably wants to spend time with his family. You gotta respect that, especially if you're fans of the show."
Mark Harmon's exit was confirmed in Monday night's episode
Elsewhere in the episode, David McCallum reprised his role as Dr Donald 'Ducky' Mallard, suggesting that viewers could be seeing more of the former chief medical examiner in the upcoming season. While his character retired from his position in season 16 of the show, he has made several appearances since then - perhaps suggesting that viewers can expect the same from Mark Harmon in the future.
Speculation that the 70-year-old actor was poised to exit were first reported by HELLO! in March when it emerged that he had entered into lengthy negotiations with CBS about his contract. According to insiders, Mark, who also serves as an executive producer on the show, was keen to hang up his gear but was informed that the network would likely end the show if he did, causing him to reconsider. As such, he agreed to return in a limited capacity and appear in just a handful of episodes of season 19.
Ducky returned in the episode to say his goodbyes to Gibbs
Following Mark's onscreen departure, NCIS showrunner Steve Binder released a statement that read: "As an executive producer and dear friend, Mark continues to be an integral part of the fabric of the show. Our north star has always been staying true to our characters, and that truth has always guided the stories we tell and where those characters go.
"So regarding the future of Gibbs, as long-time fans of the show may have noticed over the years… never count Leroy Jethro Gibbs out."
Mark, who has appeared in every single episode of the show since 2003, has yet to comment on the news of his exit. However, he did tell People back in 2019: "I've always thought if there's ever a time where the writers are walking into the room and going 'I don't know what to do,' then I think we all have to look at each other and call it a day. But we're not there yet."
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