NCIS: Gibbs vs. Fornell on just about everything
From the first time they met in "Yankee White" (Episode 1, Season 1), Gibbs and Fornell have had an ongoing turf war when it comes to NCIS versus the FBI.
However, tensions have slowly eased over the years as the two men have shared more cases—and even an ex-wife, Diane! They've grown to depend on each other for professional and personal situations. For instance, Gibbs helped Fornell cope with his divorce from Diane by taking him to a cabin for a few days to straighten out his thoughts and feelings in "Cabin Fever" (Episode 15, Season 12). But even when Gibbs let Fornell crash on his couch in Season 14, there are still plenty of barbs thrown between the two.
Watch NCIS on Tuesdays at 8/7c on CBS and CBS All Access.