Christopher Bond is an agent with British Intelligence.
At least he becomes one at the start of the hostilities of WWII. Prior to that he is known as an adventurer and, on at least one instance, a "famous criminologist".
According to The Mystery Fancier, Vol 4 #5 (Sep/Oct 1980), "Bond is an adventurer, always looking for trouble. During the war years the British use his reckless powers to combat the Nazis."
More will come when I learn more about this rare and expensive series.