In The Case of the Man on a Spot, Helen Steffans was the wife of Polish defector Ludwig Steffans. A local Suffolk girl, Helen worked in the canteen of an U.S. Army maintenance depot near Hollesey, on the Suffolk coast and was apparently well-liked by the servicemen there. Later, she married Ludwig Steffans, who had settled in Hollesey as a farm worker and lived in a cottage there.
While out on a shopping trip to the village, Helen was abducted by Communist agents and taken to Warsaw. The agents then offered to return Helen if Ludwig would return certain incriminating documents in his possession.
Biggles came to Ludwig's assistance and took a tough line with the agents, threatening to make the papers public unless Helen was returned immediately. Obviously Biggles' threat was convincing enough was the agents agreed and Helen was brought back the next day by a light aircraft. Biggles returned the documents but told them that he kept photocopies--if the Steffans were harassed again, he would make them public.