Cassie and Ronny Jennings are sisters, living a going-nowhere existence in a small town in the mountains of upstate New York. From out of the blue, they are notified of an inheritance from the father they never knew-an estate consisting of land, a house and livestock in Los Tropicos, Texas. As stated in the will, they must live there a year to legitimately claim their bequest. Cassie is excited. She's tired of the cold winters. Ronny is dubious but goes along with her younger sister, planning all along to return to New York.

In Texas, they find 80 acres of land a stone's throw from the Rio Grande River and the Mexican border, an antiquated adobe house more than 100 years old and 4 longhorn steers that their father saved from slaughter, all located 12 miles from a town with a population of 136. Their disappointment is palpable.

Their handsome neighbor, Boudreau Buckalew, a Texas Ranger working undercover, policing people and drug smuggling across the Mexican border comes to their aid more than once. Cassie, a career elementary teacher, falls head over heels and for the first time ever considers giving up her teaching career.

Next, they run into Tex Barton, a giant of a man with a heart as big as Texas, and a building contractor who agrees to do some work on the old house. He hires Ronny to be his helper. Ronny stumbles across a business opportunity she never dreamed she would have, sees her future in Texas after all and stops planning to return to New York.

Add to the sisters' culture shock is the ever-present atmosphere of drugs and people smuggling, the unexplained disappearance of food from the kitchen and a strange encounter in the house with smuggled women who appear out of thin air. In a thrilling but chaotic end, the sisters accidentally solve the mystery.