Reichsmarschal Julius Rosemeyer was a high-ranking World War II German officer who served as the Wehrmacht Chief of Staff and was an old friend of Colonel Paul Kramer. Following the capture of General George Carnaby, Rosemeyer was flown by helicopter from Berlin to the Schloss Adler to assist Kramer in questioning the American about the Allies' plans for a second front. He and Kramer ate dinner with Carnaby in the Golden Hall before proceeding to the interrogation.
Polite and courteous, he was initially hoping Carnaby would give up the information they needed without coercion, but eventually agreed to let Kramer have Anne-Marie Schwartz torture him. He took little further part in the proceedings past this point, sitting and smoking silently as Kramer had Olaf Christiansen, Lee Thomas and Edward Carraciola brought in and revealed as Nazi spies in an attempt to demoralize Carnaby, who refused to break.
Before the torture could begin, John Smith and Morris Schaffer entered. Smith, claoming to be SS agent Johann Schmidt, revealed "Carnaby" was a fraud, in reality American actor Cartwright Jones. He further claimed Christiansen, Thomas and Carraciola were also frauds, and prodded them to prove themselves by writing down the names of their fellow spies in Britain. After this was accomplished, suddenly "Schmidt" knocked out Sergeant Hartmann and held everyone at gunpoint. In reality, he was Smith, and although General Carnaby was indeed Cartwright Jones, Christiansen, Thomas and Carraciola were indeed who they claimed to be; Smith had just wanted the names of their fellow spies.
Following a further intrusion by Captain von Brauchitsch which ended with Mary Ellison getting the drop on the Gestapo officer, he and Schaffer took Rosemeyer, Kramer and the others prisoner. Rosemeyer was given a choice; be shot or injected with a knockout drug. He chose the latter. Along with Kramer, Schwartz, von Brauchitsch and the unconscious Hartmann, Rosemeyer was administered the drug and fell asleep. They were found later by soldiers sent to alert Kramer to the fact Allied agents had broken into the castle. Rosemeyer's fate after this is unknown.
- The rank of reichsmarschall (not "reichsmarschal") was only held by one man during World War II, Hermann Göring. It is more probable that Rosemeyer would've been a general or field marshal.
- In the film, Rosemeyer is a general and not a reichsmarschall, and does not survive. After Kramer is shot in the back by Schaffer whilst trying to summon help, Rosemeyer grabs Smith's dropped gun and is shot through the heart by Schaffer, dying instantly.