The Green Lama isn't quite as well known as some of his pulp contemporaries, such as The Shadow or Doc Savage, though all three transitioned into comics and other media.
In 1949, CBS Radio took a chance and tried out a radio version of the series for a short summer run. The inestimable Paul Frees, long a supporting player in a number of productions, was cast in the title role as Jethro Dumont, aka The Green Lama. Frees gave voice to almost all the male characters, including in this sample episode, courtesy of the Internet Archive:
CBS, undaunted, commissioned a TV pilot the following year, but it didn't get very far. That is to say, it wasn't made. Green Lama was meant to be a competitor to The Shadow, and Frees used his well known Orson Welles mimic to play Dumont/Lama (Welles is regarded as one of the definitive radio voices of The Shadow). I may be wrong about this, but it may be the only time Frees was actually cast in a lead role, aside from his later cartoon work.