Bulldog Drummond -- that's Captain Hugh Drummond to his friends -- ws a gentleman adventurer and World War I veteran created by H. C. McNeile writing under the pseudonym "Sapper." Xenophobia was fairly common among British (and other) writers of the Twenties, but McNeile elevated it to an art form near to A. E. W. Mason (popular author of The Four Feathers and other stories) heights. Drummond became highly popular and McNeile wrote ten books about the character; following McNeile's death, his good friend Gerald Fairlie continued the Drummond sage until 1954. (Fairlie had claimed that he was the model McNeile used used for Drummond -- well, he and McNeile's idea of what an English gentleman should be. The fact that Fairlie was a schoolboy when McNeile first created Bulldog Drummond did little to deter Fairlie from making that claim.)
Anyway, Drummond was a large success in print, on the stage, in film, and on the radio. Along the way he became more palatable, in some of the media at least. The character also influenced other writers: W. E. Johns' airman Biggles owes a lot to Bulldog Drummond, and Ian Fleming said that James Bond was Bulldog Drummond from the waist up (and Mickey Spillane from the waist down).
Bulldog Drummond hit the radio waves in 1941 on the Mutual Network with George Coulouris in the title role.The show went into syndication in 1948 and ended in 1954. In addition to Coulouris, Drummond was played by Santos Ortega, Ned Wever, and Cedric Hardwicke over the years. Throughout the show's run Drummond was accompanied by his manservant Denny, but some changes were made to the Drummond mythos: the setting quickly moved from England to America and Drummond eventually got a wife.
In the January 17, 1947 episode, "Claim Check Murders," Drummond come into possession of a claim check and a thousand dollar bill, leading to several murders and the discovery of one hundred thousand dollars worth of radium.