Two actors who play detectives on the radio find themselves investigating a real crime masterminded by an arch-criminal named the Cobra.
| Actor | Role |
|---|---|
 Wally BrownJerry Miles | Jerry Miles |
 Alan CarneyMike Strager | Mike Strager |
 Anne JeffreysEllen Brent | Ellen Brent |
 Lionel AtwillLatimer Marsh / The Cobra | Latimer Marsh / The Cobra |
 Bela LugosiStone | Stone |
 Marc CramerLt. Rick Campbell | Lt. Rick Campbell |
 Ralph DunnLt. Gilley | Lt. Gilley |
| BBilly WhiteNewsboy (uncredited) | Newsboy (uncredited) |