Mark Harmon & More 'NCIS' Stars Pay Tribute To David McCallum Following His Death

The stars – past and present – of NCIS are paying tribute to David McCallum after it was revealed that the actor passed away at the age of 90. Stars Mark Harmon, Wilmer Valderrama, Katrina Law and Brian Dietzen, as well as former series regular Michael Weatherly, all took to social media, sharing their memories [...]