Biggles is approached by Paul Cronfelt ofCronfelt and Carstairs - bullion brokers - with a proposition. Cronfelt wants him to set up an airline, a private venture with the primary object of carrying his companies' freight, namely gold and jewellery. Biggles is initially reluctant but decides to accept after receiving a threatening phone call from Germany, warning him not to. Setting up business with Algy, Ginger and Smyth as mechanic, the company is called Biggles & Co.- and as Biggles was wont to say, where there is gold, there's trouble...