NCIS Facts You May Not Have Heard

NCIS has been going strong since 2003, and the procedural show has seen all kinds of characters come and go. Mark Harmon has been at the center of it since the beginning though, with Gibbs becoming his signature character, but he actually wasn't the first choice for the role. The actor who was originally offered the role of Gibbs might surprise you, and that's just one of many surprising facts about this long-running show. From the show's popularity around the world to Pauley Perrette's qualifications for the role of Abby, let's take a look at some facts you may not have heard about NCIS.