In April 1950, the rusting hulk of a steam locomotive rises from the waters of a Montana lake, revealing the remains of three men who died 44 years before and astonishing all those who look on. In 1906, the American West has been suffering a two-year crime spree: a string of bank robberies committed by one man who murders all witnesses, and then vanishes without a trace. The US government brings in the best man they can find - a no-nonsense detective named Isaac Bell who has caught thieves and killers from coast to coast. But he has never had a challenge like this one.