There is a cab driver in LA with a mission. He kidnaps and takes on a hell ride through the desert all of his passengers he doesn't feel worthy of mankind. It is their choice then to either change their attitude towards life, work, other people, animals, or whatever it is they do that's despicable. Or they die.
On his way to work Frank, a famous and spoiled Hollywood producer, gets into a cab.
As mothers would say "never take a ride from a stranger". How can you be sure the next cab you sit in isn't the wrong one?