When war is declared in 1914, glamorous Russian Carla Vanirska manages to get to Vienna from Luxembourg, with the help of Captain Rudolph Ritter of the Austrian army. Meanwhile, Ritter is assigned to detect the identity of a spy.
| Actor | Role |
|---|---|
 Constance BennettCarla Vanirska | Carla Vanirska |
 Gilbert RolandCapt. Rudolph Ritter | Capt. Rudolph Ritter |
 Edward EllisMaj. Lieber | Maj. Lieber |
 Lucien PrivalSgt. Probert | Sgt. Probert |
 Ben Hendricks Jr.Sgt. Probert | Sgt. Probert |
 Leonid SnegoffPvt. Muller | Pvt. Muller |
 John WrayMitika, the Gypsy Contact | Mitika, the Gypsy Contact |
 Mischa AuerAgent Lehan | Agent Lehan |
| EEvelyn Carter CarringtonFrau Stengel | Frau Stengel |
| SSam GodfreyFranz | Franz |