Noah Benton, a teenager with a great memory, a head for arithmetic, and dreams of excitement, is hired along with his older brother to help drive a herd of Texas longhorns to Abilene, Kansas. But Noahs trail boss happens to be John Wesley Hardin, a notorious killer who thinks Texas lawmen wont look for a fugitive in a crew of hard-working cowboys. After Hardin sees a profit in Noahs ability to count and memorize cards in gambling dens, Noahs dreams of excitement quickly turn into nightmares -- for Hardin will kill with little provocation.