When a car bomb explodes on the American side of the U.S./Mexico border, Mexican drug enforcement agent Miguel Vargas begins his investigation, along with American police captain Hank Quinlan. When Vargas begins to suspect that Quinlan and his shady partner, Menzies, are planting evidence to frame an innocent man, his investigations into their possible corruption quickly put himself and his new bride, Susie, in jeopardy.
Following the Civil War, headstrong rancher Thomas Dunson decides to lead a perilous cattle drive from Texas to Missouri. During the exhausting journey, his persistence becomes tyrannical in the eyes of Matthew Garth, his adopted son and protégé.
Navy Commander Alan Roberts is assigned to lead an expedition to Little America in Antarctica to investigate reports of a mysterious warm water inland lake discovered a decade earlier. His helicopter and its small party, including reporter Maggie Hathaway, is forced down into a volcanic crater by a fierce storm. They find themselves trapped in a lush tropical environment that has survived from prehistoric times.
