An auto mechanic suspects sabotage in a recent series of fatal racecar accidents.
| Actor | Role |
|---|---|
 Dennis O'KeefeJerry O'Connor | Jerry O'Connor |
 Cecilia ParkerJane Delano | Jane Delano |
 Nat PendletonBuddy Buttle | Buddy Buttle |
 Harry CareyP.G. Delano | P.G. Delano |
 Addison RichardsEd Eberhart | Ed Eberhart |
 Charley GrapewinDoc Heath | Doc Heath |
 Alan CurtisJose "Rocks" Rivera | Jose "Rocks" Rivera |
 Tom NealHank Hogan | Hank Hogan |
 Tom CollinsLefty Simmons | Lefty Simmons |
 Frank OrthTim McKelvy | Tim McKelvy |
 Frank M. ThomasJim Nixon | Jim Nixon |
 Si JenksJenkins | Jenkins |
 Clayton MooreHospital Interne (as Jack Carlton) | Hospital Interne (as Jack Carlton) |
 Barbara BedfordWoman in Movie House (uncredited) | Woman in Movie House (uncredited) |
 Helen Jerome EddySusan, Laboratory Analyst (uncredited) | Susan, Laboratory Analyst (uncredited) |