Calling All Cars 34-01-24 (ep009) Case of the Three Grooved Bullets

Calling All Cars aired from 29 Nov 1933 until 8 Sep 1939 and originated on the West coast over the Columbia Broadcasting System. The show was sponsored by the Rio Grande Oil Company which was a part of the Sinclair Oil Corporation. The show only ran in areas where Rio Grande "Cracked" gasoline was sold.

The writer-director of the show was William N Robson. Each episode was dramatization of a true crime story, how each crime was solved, and justice served. Episodes were introduced mainly by officers of the Los Angeles Police Department. Sgt Jesse Rosenquist, a police dispatcher was a part of the entire run of the series.