This book started out in 1950 with the salvage operation of a locomotive from a lake in Montana. The story goes back to 1906 as it follows as Isaac Bell, a detective for the VanDorn agency, tries to find and stop the notorious "Butcher Bandit" who has been robbing banks all over the West. The bandit is very careful to leave no clues because he murders anyone who happens to be in the banks that he robs. He also leaves no tracks. The mystery is how he gets out of town.
From early in the book we know who the bandit is as we follow his exploits in trying to elude capture. The great SanFrancisco earthquake and fire help him escape.
An interesting read with a historical perspective.