A stopover in Dallas results in meeting and being hired by a seemingly upscale family, the Clayhorns from Tennessee, to guide their party and four heavily loaded Conestogas to farmland purchased by them near San Pecos. While still in Dallas, attempts are made on the lives of the Clayhorns by four would-be assassins who are then killed by Cole.
Later, during the trip west, Will senses something wrong with the Clayhorns' demeanor, but is distracted by a trio of thugs dogging their trail. When he confronts the thugs, Cole recognizes the three as a familiar old outlaw and his two equally evil sons. He and Frank Clayhorn disarm the men and take them to the sheriff in Cleburne.
Things get murkier from there. One, Clayhorn turns out to be a traitor to the South. Another, Clayhorn is later accused of having helped finance the assassination of President Lincoln.
After Cole and party reach Ft. Stockton, the climax encompasses the essence of the Texas frontier at that time. Northern and Southern Comanche, Apaches, and Kiowaall natural enemies of each otheract as one to attack the fort!