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 ...

Mark Harmon's son, portrayed a younger version of his father's "NCIS" character seven times in the main series, he did not return to play the character in "NCIS: Origins." However, that doesn't ...

Mark Harmon's son, Sean Harmon ... serving as an executive producer for the series, along with his father, who narrates NCIS: ...