Richard Damian (Arthur Hill) is a rich, selfish, rude businessman. He is traveling in the desert with his wife, Kay (Diana Muldaur), and a guide, Andy (James Stacy). He treats them like dirt. Damian falls over a low cliff and breaks his leg. Andy and Kay go for help. On the way, Kay propositions Andy. If they leave Damian to die in the desert, Kay gets his money and she wants Andy for her lover. They claim he drunkenly drove off into the desert. They crash the truck far away, so the search is in the wrong area. However, the police are a lot more clever than they expected. The police know something is wrong with the boot prints and tracks around the truck. Kay also can not hide her hatred for him.
Kay thinks Damian is a spoiled rich brat who will die helplessly in the desert. Damian sets his own leg, and makes his way back. He kills animals for food, squeezes water from cactus pulp. Kay and Andy go back to check Damian's body and make sure he died. Damian hears them talking, and learns all the details of their plan, and her contempt for him.
Damian makes it to the highway, where he is picked up by a sheriff (Michael Ansara). He tells the sheriff all the details of their plan to let him die, and mislead the search for him. Damian asks the sheriff to drop him off outside town, so he can walk in from the desert on his own, and show Kay he was strong enough to save himself.
Thanks Joseph C!