Mrs Vanester was a Dutch lady who was originally from Java, Indonesia. The postmaster at Buckbury near where she lived described her as about forty, "on the big side, and good-looking in a foreign sort of way." A milliner by trade, she had a business in Bond Street under the name "Madame Karena" which sold a line of lady's hats decorated with feathers from the Bird of Paradise (Ragiana), one of which sold for about 50 guineas. She resided in Buckbury at Larford Hall. At the time of the murder of Edmund Teale, she had been staying at the estate for 12 months.
After the body of Edmund Teale, last seen alive on a footpath at Buckbury, had been discovered on the Dutch coast a few hours later, Biggles concluded that an aircraft must have been used to transport the body. A study of the map indicated that Larford Hall had the only field large enough for aircraft in the area where Teale was walking. After seeing the Bird of Paradise feathers in the hat at the milliner's shop, Biggles spotted another Dutch connection. Birds of Paradise were considered endangered in Britain. It was almost impossible to obtain or heavily taxed in Britain. However they could be obtained in Indonesia and could more easily have made their way into Holland where they could be smuggled by aircraft to Britain. Teale might have been killed because he had seen Lurgens and his aircraft making a delivery.
Biggles checked with the Buckbury postmaster Mr Green for background on Mrs Vanester and found a link to her brother Rudolf Lurgens in Holland whom she corresponded with often. Biggles sent a telegram to Lurgens asking him to return at once, signing off as "Karena". He then proceeded to Larford Hall to wait.
At Larford Hall, Mrs Vanester denied any wrongdoing, claiming her brother had merely landed there just to visit her. He brought nothing more than a present but Biggles disputed whether the present, a parcel of feathers, would be seen by Customs in the same light. Further discussion was interrupted by the arrival of Lurgens. Lurgens resisted arrest and both he and Biggles were wounded in the subsequent shootout.
Lurgens died from complications from bursting his stitches in an escape attempt about two weeks later. Mrs Vanester was deported as an undesirable alien.