Monday’s episode of NCIS was Mark Harmon’s final one as the lead of the long-running CBS procedural. He exits the show after 18 years of playing Leroy Jethro Gibbs, dating back to the character’s introduction on JAG in 2003. Though Harmon is leaving the series, CBS’s longest-running and most watched current scripted show, executive producer and showrunner Steven D. Binder left the door open for Gibbs to return sometime in the future.
