Johnny Dollar was a detective radio show from the 40's. It centered on Mr.Dollar here, a mercenary detective that dealt with crimes ranging from fraud to murder. A couple of other good radio shows are Gunsmoke(also a show), Superman(1940), and The International Secret Police. All of these and more can be found @classicradiotheater.com, for anyone interested.
In my new book Nebulus, Flint is the main character. Flint used to be a happy guy but after tragic incidents, he became brooding. Hes merciful in battle, but he only gives you one chance at life. Beware, if he decides to kill you, it will be in a way that's full of pain.