Dennis Moore

Capt. Steve Clark

Wanda McKay

Cathy Haines

Lionel Atwill

Erich von Rugen, alias Alex Morel

Joe Sawyer

Idaho Jones

Regis Toomey

Capt. Clay Randolph [Chs. 1-6]

Virginia Christine

Countess Elsa von Merck, alias Trina Dressard

Eddy Waller

Doc Blair (as Eddy C. Waller)

Emmett Vogan

Count Manfried von Rinkton, alias Carl Lawton [Chs. 6-7]

Addison Richards

Colonel Sewell

Charles Wagenheim

Hugo Metzger, alias Abel Rackerby [Chs. 8-9]