Westy Martin and his two chums, Warde Hollister and Edwin Carlyle are on their way to the Yellowstone National Park. They stroll through the train into an empty rear car and while they are there the car is left behind and the boys find themselves stranded in the Rocky Mountain wilderness. But the train which has deserted them is destined shortly to have an adventure which, strangely enough, affords these hapless wanderers an opportunity to perform a deed of prowess and heroism. And when they finally make their way unaided to the great park they find themselves the centre of interest and admiration. 

The story of their adventures from the time they leave the deserted car to the time of their arrival in the park is one replete with thrilling episode and surprising climaxes. Then follows their adventures in Yellowstone Park. The story of how they got off the beaten track of the tourists into the remotest wilds and what happened to them there is the biggest stalking expedition that scouts ever enjoyed, is a fitting climax to the terrible experience they had during their memorable hike to the Gardner entrance of Uncle Sam's great wonderland.