Life of Tom Horn is compelling because the majority of the book recounts Horn's own life as he struck out from home at the age of 16 and became a scout for the U.S. Calvary. He was instrumental in the capture of Geronimo, went on to become a Pinkerton Detective, U.S. Marshall, served in the Spanish-American War, and also fought in the cattle and sheep skirmishes in Wyoming.

The book ends with the trial of Tom Horn for the murder of 14-year-old Willie Nickell, whose family was in the middle of the cattle and sheep skirmishes mentioned above. This section of the book is told through letters that Tom wrote as well as some personal accounts of Tom's character and information pertaining directly to the case.

This edition of the book contains the 12 original illustrations, rejuvenated.