- Milburn Stone
- Jim Hudson
- Marjorie Weaver
- Ruth Miller
- Edgar Kennedy
- Bosun Higgins
- Samuel S. Hinds
- Herman Brock [Chs. 3-13]
- Martin Kosleck
- Dr. Hauss
- Ralph Morgan
- Dr. Miller
- Joseph Crehan
- Bill Hudson [Chs. 3-13]
- Fuzzy Knight
- 'Grit' Hartman [Chs. 4-13]
- Harry Cording
- Captain Greeder [Chs. 1-3]
- Anthony Warde
- Brandon [Chs. 3-13]
- Jack Rube Clifford
- Agent Dunn, Posing as Trapper [Ch. 1]
- William Ruhl
- Agent Grey, Posing as Trapper [Chs. 1-2]
- Perc Launders
- Haegle, Fake Marshal [Ch.4]
- Edward Gargan
- Kurtz [Chs. 4-13]
- Jay Novello
- Eskimo Chief [Ch. 2-4]
- Tom Keene
- Burger [Ch. 11]
- Joel Allen
- Bob
- Ray Bennett
- Henchman
- Roy Bucko
- Miner
- George Chesebro
- Brandon's Henchman
- Edmund Cobb
- Miner Worker Preparing Ambush
- Kernan Cripps
- Marshal
- Jimmy Dime
- Driver
- Curley Dresden
- Miner
- Carey Harrison
- Cal
- Bill Healy
- Airport Official Mac
- Reed Howes
- Ship's Officer
- Bill Hunter
- Deputy
- Jack Ingram
- Henchman Kruger
- Walter Lawrence
- Seaman
- Artie Ortego
- Henchman
- Edward Peil Sr.
- Mine Watchman
- Stanley Price
- Brandon's Henchmen
- Jack Rockwell
- Kessel
- Dick Rush
- Henchman
- Cap Somers
- Workman
- Clarence Straight
- Pilot
- Charles Sullivan
- Deputy
- Ben Taggart
- Deputy Marshal
- Jean Trent
- Secretary
- Carl Vernell
- Co-Pilot
