- Robert Livingston
- Dr. Lawrence Baxter
- Grace Bradley
- Jean Sterling
- Willard Robertson
- Inspector 'Mac' McDonald
- Pierre Watkin
- Kennedy
- Smiley Burnette
- Jimmy
- Granville Bates
- Prof. Rexford Sterling
- William Newell
- Andrews
- Byron Foulger
- Pete Andorka
- Wilbur Mack
- F. J. Thompson
- Matty Fain
- Burke
- Josephine Whittell
- Nurse Nelson
- Charles Timblin
- Swain
- Billy Griffith
- Kellogg
- William Hopper
- Announcer
- Frank Du Frane
- Golden
- Florence Gill
- Spinster
- Frank Austin
- Henchman
- Richard Beach
- Henchman
- Harrison Greene
- Hospital Administrator
- John Holland
- Druggist
- Monte Montague
- Henchman
- William H. O'Brien
- Nightclub Waiter
- Mary Russell
- Nurse
- Carleton Young
- Radio Announcer
