Biggles Defies the Swastika has Biggles trapped in Norway by the Nazi invasion during World War 2. His initial efforts to escape the country are to no avail once Colonel Raymond finds out of his whereabouts and encourages him to be remain as a spy.

Whilst continuously complaining about the underhandedness of it all, Biggles makes a fantastic spy, getting himself promoted to Gestapo officer and single-handedly saving the British invasion force from a trap set by Erich Von Stalhein (who else?). He is almost helped by Ginger and Algy but for every time they get him out of one problem, they get him back into two others.

Not only does Biggles manage to escape from Erich Von Stalhein's clutches (twice) he uses his car and his aeroplane to do it. Talk about rubbing salt in the wound!! There is also a nice touch where Biggles is treated well by a German officer who he later captures. On releasing him he offers him dinner at the Aero Club after the war.