Brann Wimmer isn't actually a Nazi. He's an undercover American agent. But where did he get his Nazi uniform(s)? Why from this poor sucker named Gunther, of course! He ambushed him in an alley, overcame him in a fighter, stripped him to his undies, tied him up, and how he's looking spiffy in Gunther's SS hauptsturmführer's uniform, ready to fool a whole lotta high-ranking Nazis (and seduce one in particular), all to change the course of the war however he can.