Finding a skull on a camping trip in the canyons outside El Paso, Texas, Brennan becomes involved with the fate of a young Apache Indian who lived in the late 1800s.
In 1684, wearing his father's faded cap, eleven-year-old Pierre Talon joins explorer Rene-Robert Cavelier on an ill-fated expedition to seek the Mississippi River, but after the expedition falls apart Pierre, deathly ill, is taken in by Hasinai Indians. Includes historical facts.