Tia and Tony are two orphaned youngsters with extraordinary powers. Lucas Deranian poses as their uncle in order to get the kids into the clutches of Deranian's megalomanical boss, evil millionaire Aristotle Bolt, who wants to exploit them. Jason, a cynical widower, helps Tia and Tony "escape to witch mountain," while at the same time Tia and Tony help Jason escape the pain of the loss of his wife.

A dog that is a minion of Satan terrorizes a suburban family.

In Las Vegas, the regenerated ex-con Jack Bruno works as taxi driver. During an UFO Convention at Planet Hollywood, the skeptical Jack picks up Dr. Alex Friedman, who will present a scientific lecture in the event. Then he is pressed by two henchmen of his former boss, the criminal Wolff, that wants to talk to him, but Jack does not want to return to the crime life. Jack fights and gets rid of them; out of the blue, he finds two teenagers on the backseat of his cab. They tell that they are siblings, Sara and Seth, and they need to travel to a location outside Las Vegas in the middle of nowhere. Meanwhile the government finds a spacecraft that crashed nearby Las Vegas and is chasing the two aliens; after the investigation of the men of Major Henry Burke, they discover that the two siblings are the aliens. Jack Bruno, Sara and Seth are chased by Henry Burke's team and by the "Syphon"...