This could be read by a slightly younger age group since it's an obvious adventure tale but with lots doing in the story of two young men, engineers, one American and one English, in the England of 1969. Lost on a trial flight, Van, the American, lands on a strange airfield -- and becomes curious about a secret international organisation operating on the radio beam PX. Persistent shadowing reveals PX to be a peace-minded movement, Van and Heaton join it, use their plans for a super-speed plane to get the interest of two Middle European dictators, kidnap them and prevent a new war crisis. O.K. no more, no less.