Why Mark Harmon Almost Quit NCIS During Season 4

Mark Harmon has left NCIS after 18 full seasons, but he almost quit the show back in 2007 during season 4. Throughout the series’ impressive run on CBS, various stars have come and gone, like Michael Weatherly and Cote de Pablo, but Harmon has been the glue holding the team together, both on and off the screen. He’s also been an executive producer on NCIS since the show started in 2003.

His departure during season 19 has raised questions of whether NCIS can survive without Harmon’s Gibbs, but it’s especially tough to imagine how the show would have fared had he left after only four years. As it currently stands, NCIS is well-established as one of the most-watched network shows in the country and has a loyal base of followers, many of whom have been tuning into the procedural drama for nearly two decades. It could fare well enough without Gibbs as Special Agent In Charge. However, had Harmon quit the show during season 4, NCIS may not have become what it is today.