From February 12, 1947, an episode of The Adventures of Ellery Queen with guest "sleuth" Jose Ferrer.
Ellery Queen first hit the radio waves as a detective in 1939. The show went through a number of cast changes, networks, and sponsors over the years. This episode was on NBC Radio and sponsored by Anacin. Lawrence Dobkin played Ellery, Bill Smith played Inspector Queen, and Charlotte Keane* played Nikki Porter. The script was by Manfred Lee and Tom Everitt.
The Green Gorillas of the title are a gang of juvenile deinquents run by a self-styled Fagin -- that is, until Ellery intervenes.
* Not Kitty's aunt. That Charlotte Keane is in her late eighties and is alive and well in Coeur d"Alene. A wonderful person.