"... and how is your Wing-Commander's eldest daughter Penelope?" The explanation reads: "On arriving in Germany the dazed and bewildered prisoner was quickly interrogated by the Germans, who by means of bogus Red Cross forms and other tricks attempted to extract information of military importance."

 

This illustration is taken from "Handle With Care" by R. Anderson and D. Westmacott, a book of sketches made by Prisoners of War.