A vagabond family composed of Pop Kwimper (Arthur O'Connell), his son Toby (Elvis Presley), and various "adopted" children, including sixteen-year-old Holly Jones (Anne Helm), are traveling in Florida when Pop drives onto an as-yet-unopened section of highway. When the car runs out of gas, Holly persuades Pop to take up residence on the land next to the road. A chance encounter with an avid fisherman (Herbert Rudley) gives Holly an idea. They soon build up a thriving business catering to sports fishermen.
However, trouble soon follows. When Toby rejects the advances of amorous social worker Alisha Claypoole (Joanna Moore), she goes to court to have the children taken away in revenge. Also, her government official boyfriend considers them to be an eyesore and wants to evict them. Finally, since the area is outside the jurisdiction of any law enforcement, two gamblers (Jack Kruschen and Simon Oakland) soon set up a casino in a trailer. In the end, Toby's earthy wits and family resolve win over the judge and the family returns to its new land and home. With Alisha's help, Holly gets Toby to recognize that she is a grown woman and that he loves her.