Mark Harmon has come a very long way from his very first acting jobs.
The former NCIS star has been in the business since the early 1970s, and aside from his role as Special Agent Leroy Jethro Gibbs on NCIS, which he played for almost 20, he is also known for his roles in The West Wing and Freaky Friday, among others.
And though his acting debut is technically considered the show Ozzie's Girls, which ran from 1972 to 194, before that, he had a different, somewhat "humiliating" intro into acting.
Several years before making his debut on Ozzie's Girl, Mark, then barely a high school student, made his commercial debut for a Kellogg's ad, alongside his dad Tom Harmon.
Tom, who passed away aged 70 in 1990, was a football player, for the Michigan Wolverines and the Los Angeles Rams, as well as a pilot during World War II and later a sports commentator.
He was also for a time a spokesperson for Kellogg's discontinued cereal Product 19, which was sold from 1967 and 2019, and it was for that product that Mark made his very first commercial.
Speaking about the experience during a taping of LIVE with Kelly and Mark, which for the week aired from Palm Springs, Mark recalled: "My dad was a spokesperson for Product 19 and so I was in a commercial, in the backyard eating cereal," and joked: "Which, that never happened."
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Host Kelly Ripa, thinking what her three kids with husband Mark Consuelos would have been like in that situation, as if it was "embarrassing" for him, to which Mark confirmed: "Yes, humiliating."
Though he noted that people did not start recognizing him because of it, it did "change my direction a little bit, I think, I saw something, that crew, those people around that I understood," indicating his subsequent proper entry into the acting world.
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Co-host Mark then asked whether he had gotten paid, to which he said he did not, and as he suggested, "I think they have laws against that now," Mark lastly joked: "Not then!" with a laugh.
Mark left his gig on NCIS after 18 seasons in 2021, and has since then focused on another, somewhat related passion of his, writing history books. In 2023, he wrote Ghosts of Honolulu: A Japanese Spy, A Japanese American Spy Hunter, and the Untold Story of Pearl Harbor, which includes a retelling of what led to the birth of the real NCIS, and most recently, Ghosts of Panama: A Strongman Out of Control, A Murdered Marine, and the Special Agents Caught in the Middle of an Invasion.
He also still works with CBS as an executive producer of NCIS, as well as for prequel series NCIS: Origins, in which Austin Stowell plays a younger version of his character Gibbs, for which he also serves as a narrator.