A man receives becomes able to heal people (and revive the newly-dead) with his touch.
Earth is the repository of the most valuable substance in galaxy, the prime ingredient for making the only known aphrodisiac, salt water. By galactic rule, we must prove ourselves ready for the great wealth to come, lest we destroy ourselves and take half the galaxy with us.
An experiment is conceived. Starship Pilot Doe Ray Mee and Mission Commander Ala Mode travel to Earth, to gauge our readiness.
John Hightower, a homebuilder, comes to realize he has somehow gained the power of healing others. As events unfold, he is proclaimed by some to be The New Messiah, by others as the greatest fraud of all time.
He is exploited by the media, the political establishment, the legal system, and organized religion.
After a series of unfortunate events, the situation deteriorates, he is declared the anti-christ.
Enraged fanatics attack his home and attempt to stone him to death. In a break with protocol, he is rescued and taken to safety back to Malibu, (along with ten gallons of salt water and his wife), making them extremely wealthy.
Alas, there's no place like home.