JEFF BRIDGES and Karen Allen costar in "Starman," John Carpenter's version of the Greatest Story Already Told. Allen is a modern-day Mary and Bridges a fertile messenger from the heavens. This time the conception isn't immaculate. It occurs in a freight train somewhere outside Las Vegas.

If Erich Von Daniken rewrote the nativity, this would be it, a sometimes sweet, sometimes sappy, finally implausible blend of "Chariots of the Gods," "E.T.," "Close Encounters" and the Bible.

Bridges, as the likable father of the future messiah, was invited to Earth by Carl Sagan. He finds a platter in a space satellite, and after listening to a recording of the Stones' "I Can't Get No Satisfaction" and greetings from earth in 54 languages, he decides to visit. On the way, his ship is intercepted and shot down, and he is, of course, pursued by scientists who want to dissect him.

The Starman falls to earth in a remote part of Wisconsin, clones himself from the hair of a deceased house painter and begins a journey across country with the painter's widow, a human's human played by the accomplished Allen. The alien, unaccustomed to his new body, moves awkwardly at first, and though he never quite gets the hang of sneezing, he is able to hit his mouth with a fork. Bridges, using an altered Russian accent and mechanical motions, makes a quirky, other-worldly success of this mission.

Starman must get to the mother ship before he dies in three days. Along the way, between pies at the truckstop, resurrecting a deer, and several not-so-close scrapes with various Highway Patrolmen, the alien and the earthling fall in love. And they do get some satisfaction.

Despite Allen's sincere face; Bridges' quirky, effective portrayal; some exquisite effects; and many funny moments, the film falters at the finish, if not a little before. Mostly it never delivers what it promises -- an alien with all the right answers.

If we are not alone, then "Starman" isn't either. This season's crop of super beings are fairly dim bulbs. In "2010," Keir Dullea promises, "Something wonderful is about to happen." In "Dune," Kyle MacLachlan says, "The sleeper will awake." And now "Starman" is here to tell us, "You're at your very best when things are worst."

Yes, quite the message for Christmas. Thanks. Have a Nice Day. STARMAN -- At area theaters.