David McCallum's credits include over 30 books on tape and CD, and his portrayal of Illya Kuryakin in "The Man from U.N.C.L.E.," for which he received two Emmy Award nominations. His many theatre productions include "Amadeus," "Communicating Doors," "The Hunting of the Snark," "Comedians," "The Lion in Winter" and "Julius Caesar." His many television appearances include "Sapphire and Steel," "Colditz," "Trainer," "The Education of Max Bickford," on CBS, "VR5," "Motherlove," "Kidnapped," "The Invisible Man," and episodes of "The Outer Limits," "Law & Order," "Sex and the City." He plays the role of Dr. Donald Mallard in the CBS series NCIS.
Doctor Donald "Ducky" Mallard is NCIS' Scottish Chief Medical Examiner, who often accompanies Gibbs' team into the field for the collection of bodies and body parts. With a habit of talking to the corpses upon which he performs autopsies, as well as his penchant for excessive exposition on vaguely-related topics, Dr. Mallard proves very qualified to both assist and entertain the agents for whom he works. Early in season 4 Ducky gets his Masters in Forensic Psychology. Mysteriously after what was indicated to be a long and respecting friendship with Gibbs, recent events seem to have caused a rift in this friendship, with the tension between them getting progressively stronger since Gibbs' decision to return to NCIS.