Mitchel Becker ventures in Versailles, France days before the Nazi occupation, confident he can get out before the Nazis invade. It isn't the first time he's been wrong. Then he meets Kirsche. He doesn't realize she is a trained Gestapo assassin.
Enter Burns of Army Intelligence who coaxes Mitchel to play into Kirsche's hands, letting her help him escape Nazi occupied France into Switzerland where Kirsche abandons him.
Burns then tells Mitchel he must go to Singapore to protect Jacob Haro, a scientist who has defected from Nazi Germany and the secret project he was assigned to, the V-1 buzz bomb. Mitchel doesn't know the man he is protecting is the man Kirsche is assigned to assassinate.