The Jackson brothers have driven a herd of cattle from Texas to Shiloh that Clay Grainger hopes to purchase. Clay and his wife Holly also from Texas have taken over from John who is away on business. However, Trampas believes the cattle may be infected with Blackleg fever which he noticed when he and Clay visit Kyle Jackson at the herd. At the same time Hattie McLain and her son Johnny leave their remote ranch and her husband Sam a retired but renown Texas marshal to deliver a string of horses to Shiloh and pickup supplies at Medicine Bow. The two younger Jackson brothers go to Medicine Bow to celebrate and while drunk they have a shooting contest. The younger brother Willy accidentally kills Hattie when a ricochet hits her. Ryker arrests the two brothers just as Kyle learns the herd may be sick and must be quarantined. It soon becomes apparent to Kyle that even if some of the herd survives, he will loose the herd due to feed costs. At the same time Sam McLain wants revenge for the ...