Biggles flies again into adventure in the far places of the earth. Stranded among the tropical swamps of British Guiana when the company employing him as a pilot folds up, he takes possession of the amphibian aircraft he is flying and proceeds to earn his living by undertaking dangerous missions by air. With Algy and Smyth, he searches for treasure in the jungle, captures a brigand-chief in his own mountain stronghold, leads a pearling expedition into a fantastic reef-bound lagoon, shanghais a Russian agent on an Arabian island, and trades pearls with a desert sheikh on the Red Sea coast.