Rupert Saint Leger inherits his uncle's estate worth more than one million pounds, on condition that he live for a year in his uncle's castle in the Land of the Blue Mountains on the Dalmatian coast. There Rupert tries to win the trust of the conservative mountaineer population by using his fortune to buy them modern arms (from a South American country that has unexpectedly found itself at peace) for their fight against Turkish invasion (the story was written shortly before the Balkan Wars).