FRYEAN MYTHOS: *drama*
CAMPBELLIAN FUNCTIONS: *cosmological*
Fred Gebhardt had a very short career as a writer and producer in movies, with just four movies to his credit on IMDB. Prior to making this movie, he made the remembered-only-by-hardcore-fans TWELVE TO THE MOON. for which he functioned both as producer and writer of the original story, just as he does in PHANTOM PLANET.
I don't remember liking PHANTOM very much in earlier viewings, but I found it a bit more winsome this time around, despite recognizing the story's indebtedness to 1955's THIS ISLAND EARTH. No one will ever consider PHANTOM classic science fiction. However, I did find that Gebhardt, whatever his personal opinion of the genre, succeeded in putting forth some of its "gosh-wow" appeal, albeit on a small budget.
The "planet" of the title is actually an asteroid called "Rheton," inhabited by humanoids who were implicitly once as big as Earth-people, but who shrank down to tiny-size due to the combined effects of their special atmosphere and the gravitational controls that they use to steer their "ship." However, the Rhetonians aren't always able to avoid other space-craft.
For Earth, it's the year 1980, and there's a flourishing space-program based on Earth's moon, apparently just to give the sense of the advances made. (PHANTOM is one of the few movies of the period in which there are assorted Earthmen but no actual scenes on Earth itself.) In the film's opening scenes, one Earth-ship has already been destroyed by a mysterious "phantom planet," and another such ship, manned by two American astronauts, is annihilated in the first five minutes. Nothing daunted, the Lunar Agency sends out another ship for reconnaissance, whose two-man crew consists of Captain Frank Chapman and his navigator Lt, Makonnen.
The viewer doesn't have much time to get to know Makonnen. He has a few philosophical lines about how people should pay attention to "the good and the beautiful." Then the ship encounters, but does not crash into, the Phantom Planet. A meteor shower does hit the ship, though, and when the two astronauts do a space-walk to make repairs, Chapman's air-hose is holed by a mini-meteor and another such projectile wounds Makonnen. Makonnen managed to hustle the unconscious Chapman back into the ship and shut the door before he Makonnen drifts into space, praying to his deity as he perishes. Chapman returns to consciousness in time to realize that Makonnen must be dead and that his ship has now been caught by the gravity field of Rheton.
Chapman lands the ship and ventures out onto the asteroid's surface, finding that it possesses an atmosphere. Still weak from his experiences, Chapman collapses, and the native Rhetonians-- all male so far-- swarm around his Gulliver-sized body. Then the atmosphere gets into Chapman's suit and shrinks him down to mite-size. He revives just as the Rhetonians approach, and he fights back a little before they subdue him.
The leader of the Rhetonians, one Sessom (more or less "Moses" spelled backward), tells Chapman he's never going to see Earth again, and that he must become a productive citizen on Rheton. Presumably most of the men seen earlier were married guys, since Sessom informs Chapman that as a citizen he's free to court one of two women-- Sessom's daughter Liara and a mute girl named Zetha-- who are apparently the only marriageable ladies on Rheton. The women are not consulted, but they're both very interested in Chapman, with the talkative Liara taking the lead by giving Chapman the nickel tour. Over time Chapman finds out some interesting bits of history. The Rhetonians once depended too much on their advanced technology and "grew weak." However, they reversed this tendency-- possibly as a result of taking off in their own gravity-driven asteroid-- and began to live lives of comparative simplicity. (This strategy also gives Gebhardt an excuse for keeping the settings and costumes simple as well.)
Chapman has another problem in addition to his enforced citizenship, for Liara does have another suitor, an irritable fellow named Herron, who accuses Chapman of being in league with Rheton's not-yet-seen enemies, "the Solarites." This ought to work to Chapman's advantage, since he's become smitten with the silent, "sensitive" Zetha as against the somewhat privileged Liara. However, Chapman doesn't like being insulted, so the two of them fight a duel according to Rhetonian law, in which the combatants try to force one another into "gravity planes" full of disintegrating energy. Chapman wins but spares Herron. The Rhetonian then rewards Chapman by trying to help him get back to Earth, though not without some self-interest, to get rid of competition. However, with that conflict out of the way, Rheton is tracked down by the Solarites. Sessom uses the planetoid's superior technology to repel the invasion, but the violence releases the one Solarite prisoner held by the Rhetonians, and he provides some last-minute menace before being killed. Chapman, though he wants to remain with Zetha, cleaves to his military duty and returns to Earth, after which he has only minimal proof that what he experienced was real.
The Rhetonian-Solarite quarrel is really the only element cadged from THIS ISLAND EARTH, but it's not entirely a rip-off. I thought it interesting that the Solarites are called "fire demons" and that they use "heat bombs" to attempt destroying the gravity-mechanisms of Rheton. One might say that these fiery associations give them the role of devils as against the "angelic" Rhetonians. Even the Solarites' motives for attack-- they want to steal the gravity-tech in order to keep their own planet from falling into its sun-- sounds a bit like the attempt of evil demons to escape their own hell.
That said, PHANTOM is more concerned with Chapman's problematic adoption by another culture, and his determination to get back to his own world, despite the temptations of Liara and Zetha. Liara, Herron and Sessom are not particularly well developed, though. There's an odd subplot in which it's revealed that Zetha became mute due to the same Solarite incursion that left one living Solarite prisoner on Rheton. Apparently Gebhardt wanted to give her a "trauma breakthrough" moment, since at the film's end she recovers his original speaking-voice as the result of being briefly abducted by the Solarite. However, Gebhardt isn't as good with the big dramatic moments as he is with small ones, as when Chapman and Zetha have to bid one another farewell. That said, Rheton, not Chapman, is the "main character" of PHANTOM PLANET.