A rescue team from earth lands their flying saucer-like spacecraft on an alien world, to discover they are not only not welcomed by the lone survivor of a missing scientific expedition sent there two decades earlier, but, once they have determined to investigate the deaths of his colleagues and bring him back home by force, along with his planet-born daughter, find themselves subjected to assault by something invisible which seems intent on preventing them from leaving the planet, ever.

An authoritarian rancher rules an Arizona county with her private posse of hired guns. When a new Marshall arrives to set things straight, the cattle queen finds herself falling for the avowedly non-violent lawman. Both have itchy-fingered brothers, a female gunman enters the picture, and things go desperately wrong.