After 18 years of leading “NCIS,” Mark Harmon has stepped away from his high-profile camera role on the popular CBS criminal drama.

Monday’s episode of “NCIS,” the fourth episode of Season 19, concluded with his character Leroy Jethro Gibbs, who was nearly killed in a boat explosion in the Season 18 finale, deciding not to return to his job in NCIS. “I’m not going back, Tim,” said Gibbs to Special Agent Timothy McGee (Sean Murray). Gibbs instead chose to remain in Alaska, where he and McGee tracked down a hitman hired by a local company.

Executive producer and showrunner Steven D. Binder left the future ambiguous as to whether or not fans would see Gibbs again, noting that Harmon is executive producer.

“As an executive producer and dear friend, Mark continues to be an integral part of the fabric of the show,” Binder said in a statement. “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.”

Harmon was first introduced on the show “JAG” in 2003 and will remain a producer for “NCIS.”

Season 19 introduced new character Special Agent Alden Park, played by Gary Cole, and new series regular Special Agent Jessica Knight, portrayed by Katrina Law. They will star along long-serving cast Murray, Brian Dietzen, Rocky Carroll and David McCallum, as well as the more recently added regulars Wilmer Valderrama and Diona Reasonover, who joined Seasons 14 and 15.