When Colonel Raymond is handed an unsolvable case of a criminal mastermind at work in England, it takes Biggles and the team all of two chapters to work out the culprit is Lord Malboise. The rest of the book is taken with the team trying to find enough proof to gain an arrest. Highlights include Ginger dressed as an Indian princess (described as looking like a "smart, good-looking young woman"), avoiding buffalo in a Sussex country estate, and calling for help using paper aeroplanes

And the bad guys use a helicopter to move their contraband out of the country. That's in case you're wondering what the relationship is with the Special Air Police.