The fourth in the series of Homer Evans mystery adventures takes the reader for the ride of his life all the way from Paris to the badlands of Montana. In the wide open spaces where the last survivors of be Blackfeet and Shoshone Indians still keep their tribal ways in the lower stretches of the Yellowstone, where sheepherders and cattlemen fight to the death on the lone prairie, where behind every clump of sagebrush a dead-eye marksman lurks, there go all the veterans of the bloody campaigns in The Mysterious Mickey Finn, Hugger-Mugger in the Louvre and Mayhem in B-Flat. Guided by Rain-No-More, the Blackfeet son of a chief, directed by the ever-resourceful Homer Evans and trigger-quick Miriam Leonard, and supported by Hugo Weiss the financier, Hjalmar Jansen, the scourge of the studios, Frémont of the Paris police, Anton Diluvio the virtuoso, and all the tried and true shock troops of the previous books, they travel by ship and special train to the frontier battleground. They arrive just in time to participate in the first skirmishes between the cattlemen's forces and the sheepherders' mercenaries recruited among the Great Lakes palefaces, all of them trained braves who had had their baptism of tommy-gun fire in Chicago's gangland wars. The casualties among cowboys, Indians, trigger men, sheep and cattle are appalling. But Homer Evans, by a stroke of tactical genius, turns defeat into victory and forever puts an end to lawlessness in the badlands.