The audio in games is as important as the video in drawing players into the story and keeping them fascinated. The original Gunsmoke radio drama made excellent use of narration and sound effects to move its plots forward, and is worth studying for its use of audio cues.
The radio show was much edgier than the television show it spawned, and dealt with many topics off-limits to the television series, including prostitution and drug addiction.
This is the first episode of the series, licensed by the Old Time Radio Research Group under the Creative Commons Attribution-NonCommercial-NoDerivs license. You can listen for inspiration, but can't use it in derivative products.