Born in 1933, McCallum certainly emerged prominently in genre circles in the role of 'Illya Kuryakin' aboard the great 1960's spy show The Man From U.N.C.L.E. (1964-1968), but that was far from his only work in the realms of the Fantastic. He had many opportunities to show what he was capable of doing in ways big and small, and I'm happy to name some of the more memorable adventures below.
In the 1963-1964 TV season, the actor enjoyed a pair of appearances to The Outer Limits, cast in different roles aboard the episodes of "The Sixth Finger" and "The Forms Of Things Unknown."
In 1970, McCallum took on the role of Hillel Mondoro, a scientist who injects himself with the brain fluid of a terminal colleague in order to protect some defense department secrets. As you can guess, this medical event has unintended consequences that start to work their way into the man's daily life. The Hugo Award nominated telefilm also starred Susan Strasberg and Leslie Nielsen.
For the 1975-1976, he took on the role of another scientist, this one who experiments with a serum that gives him the power of invisibility. The Invisible Man lasted only a single truncated season, but it's one of the fond memories of my TV youth.
Alas, I've never seen Sapphire & Steel -- a SciFi/Mystery serial that paired McCallum with actress Joanna Lumley -- but I've been assured it's quite good. Some have even told me that the series feels in ways like a precursor to The X-Files as these interdimensional operatives would step into our world to solve mysteries only they possessed knowledge to decode.
In 1995, he joined the cast of the virtual reality drama VR.5 playing yet one more scientist (it would seemed he played men of great intellect) working on the project to use this fledging science to do good.
As is always the case, there are more -- quite a few across the man's career spanning an incredible seven decades -- and readers are encouraged to check out his full profile on IMDB.com. It's indeed quite an impressive and versatile roster, and our world is a smaller place with his departure.
Prayers are extended to the family, friends, and fans of David McCallum. May be rest in peace.