To walk the shadow trail means to lead a life of pain and sorrow, to be alone forever.

Many men came to America to escape their old lives. Baron Karl Augustus Dietrich Wilhelm von Brandt was no different, though he fled his father's crimes and not his own.

Easily swindled into buying a Nebraska ranch that's little more than a sand dune, the European tenderfoot is befriended by half-Pawnee Johnny Moon, a ne'er-do-well usually one step ahead of the marshal. Soon Johnny has Will looking and sounding like a Nebraskan. Working together, the impoverished nobleman and the half-breed cowboy transform the ruin into a thriving ranch. Through tough times and good Johnny Moon is there for Will, closer than a friend, trusted like a brother.

Then Will marries Silent Summer Woman, the headstrong daughter of a Pawnee chief, and the first wedge of mistrust is driven between the two men, for Johnny Moon is harboring a secret, and if Will discovers it, not only will it destroy their friendship but also their lives.