If Biggles had not taken a quiet holiday on the Cornish coast, a highly professional gang of smugglers might never have been brought to book.

As it was, a slight suspicion about a shark-fishing expedition led Biggles, helped by Ginger, Bertie and Algy, to make discreet inquiries in the area, expecially about Julius Brunner, the owner of an expensive Daimler, and his activities in shark-fishing and hotel ownership. Although the crooks were skilful and ruthless, they found only disaster waiting for them on one of the smaller islands in the Channel, where they had fled with Biggles in hot pursuit.