Two English servicemen in flight from German troops in WW I Africa (The Cameroons): sturdy, fairly lighthearted chase-action--featuring lots of cinema-styled hijinks with a barely-functional aircraft. There are three Britishers when the story begins, all of whom are captured by Oxford-educated Max von Graben on Ndinga Mountain: upper-class Capt. Cunningham; middle-class Lieutenant Poynter; lower-class Able Seaman Smith. And the three soon manage to escape from the Germans--determined to reach British Nigeria with the crucial war-data they've just acquired: the whereabouts of the Germans' biggest wireless station in Africa. But, as the British trio arrives at a German mission and appropriates a six-cylinder flying machine stored there (the ""Dove""), von Graben and his men are in close pursuit; and though the Brits manage to take off in the plane, Cunningham is fatally shot. So, for the rest of the chase, it's just Poynter and Smith--who, en route to the Nigerian border, use the ailing Dove as a glider, a ground vehicle, even as a railroad car and a sailing vessel. Meanwhile, von Graben is always close behind or circling around to cut them off at the pass--though he is increasingly distracted by Irish nurse Regan, whom he has more or less abducted (because she, too, now knows the secret of the wireless station). And there's an ironic, large-scale naval finale, which draws more than a little inspiration (as do a few other episodes) from The African Queen. More fully satisfying, in fact, as an old-fashioned film scenario than as a novel--but solid adventure-entertainment in the worthy-rivals, stiff-upper-lip tradition.