Walt Slade, ace lieutenant of the Texas Rangers, is the man most feared by the owlhoots and drygulchers of the old Texas Border. The sight of this tall lawman with the lightning-fast draw astride his great black horse, Shadow, symbolizes defense of the innocent and the end of reckless careers of lawlessness. Walt travels undercover, keeping his Ranger status a secret. To many, he is known as El Halcon and believed to be an owlhoot who is too good at what he does to be caught.