Producer Don Bellisario understood this formula and bet on it during the casting process, especially when choosing David McCallum for the role of Donald Mallard, also known to his colleagues as Dr.

NCIS fans adored David McCallum in his role as Ducky, but studio bosses reportedly were not happy with the decision to cast the Scottish actor in the role ...

David McCallum almost didn’t get cast as Ducky on NCIS, but decades later, he became one of the show’s most beloved ...