This is the latest installment in a well-established Western cop series. The cop is Page Murdoch, U.S. marshal, cynic, tough-ass, and the last man you'd want on your tail. In this book Murdoch, Montana-based, pursues a vicious gang into the far north of Canada in winter--the infinity of snow he encoutners gives the title White Desert. To get his men he must outwit or outmaneuver some aggressive, unpredictable Metis; goes into a colony of American blacks escaped from slavery and still touchy; and a band of Sioux, followers of Crazy Horse fled to Grandmother's Land for safety.