Astronomers discover a comet that they believe will crash into Phoenix, Arizona. They attempt to warn officials, but without 100% certainty, the governor of Arizona is reticent to cause a panic. Even after a television news reporter discovers the truth and threatens to go live with it, the response is understated enough to doom some residents of Phoenix to certain death.

Jeremy Rodock is a tough horse rancher who strings up rustlers as soon as looks at them. Fresh out of Pennsylvania, Steve Miller finds it hard to get used to Rodock’s ways, although he takes an immediate shine to his Greek girl Jocasta.