In 1954, the first controlled fission reactor promised a seemingly endless supply of electricity to the U.S., and Raymond Jones' novel, This Island Earth, was adapted to the screen. While Jones' innovative idea of an assembly test remained, the soon-to-be-replaced screenwriter George Callaghan added his own loopy touch: the manipulation of matter through neutrino waves.
Neutrinos are notorious for passing through entire planets undetected. Yet the Metaluna aliens use these sub-atomic particles to fly planes, destroy matter and communicate with each other via an "interociter". Despite the lousy science, This Island Earth opened to rave reviews, and only several decades later would MST3K: The Movie suggest that the film was inherently flawed.
We are introduced to our hero, Dr. Cal Meachum (Rex Reason), when he cracks wise with reporters about the benefits of atomic energy ("What counts is how I make it work"). Ego firmly intact, Cal hops in his plane, flies to LA and loses control on landing. Seconds before impact, a green neutrino beam surrounds the plane and sets it down safely on the runway.
Shaken, Meachum returns to his lab where he demonstrates an electronics skill nearly equal to his aviation skill by blowing up a condenser (or, as Mike and the 'bots note: "This is when science had no specific purpose").
The condenser replacement order is intercepted and filled with handful of red, glass beads. While Cal blows up the micro-condensers, a book arrives detailing the assembly of an interociter. He abandons the beads and orders all 2,486 parts of the interociter (surely a precursor to IKEA), which are sent free of charge with the caveat that nothing will be replaced.
After successful assembly, a peroxided man with a misshapen forehead appears on the interociter screen. This is Exeter (Jeff Morrow), an alien who is recruiting scientists (he'll later recruit The Last Starfighter and Jodie Foster via Carl Sagan's ship in Contact). He sends a neutrino-powered plane for Cal and proves his superior technology by blowing up the interociter and assembly plans remotely. Cal is impressed.
At Exeter's lab, Cal runs into Dr. Ruth Adams (Faith Domergue), an old flame who suspects him of being brainwashed by Exeter. Exeter's assembled the Earth's top nuclear physicists and plans to end war by accumulating a large amount of uranium. Cal is the jewel in Exeter's crown, as the latter-day alchemist has found a way to convert lead into uranium (presumably by reversing the U238 to Pb206 decay).
Suspicious of Exeter's plan, Cal intercepts Ruth and Dr. Steve Carlson (Russell Johnson, light-years from his final island abode) for a frank discussion about their benefactor. Apparently Exeter has a nasty habit of brainwashing dissident physicists and has discovered the missing link between energy and matter: the neutrino (and here Einstein had us thinking it was the speed of light squared).
The next day, Cal, Ruth and Steve flee the labs. Exeter has received an abort mission command from Metaluna and starts destroying the scientists and lab. Steve is killed and Ruth and Cal flee in the plane, only to be abducted by Exeter's spaceship via a neutrino tractor beam.
En route to Metaluna, Cal and Ruth readjust their gravity via smoke-filled tubes and Exeter reveals his true need for the uranium: to replenish crumbling shields on Metaluna. The hostile planet Zahgon has been bombarding the surface with comets and their nuclear-powered shields are crumbling. Tellingly, not one word is mentioned about using nuclear power to launch an atomic attack against Zahgon.
On Metaluna, the head Monitor has come up with an even better survival plan: to relocate to Earth and rule the brainwashed inhabitants. He sends Exeter with a Mutant escort to brainwash Cal and Ruth.
Fortunately, Exeter has a change of heart and saves Cal and Ruth from their lobotomy. They flee the planet in time to watch it's final destruction. Exeter waxes nostalgic about Metaluna bringing warmth to the galaxy, and Cal and Ruth neglect to point out that Zahgon would be the only true beneficiary.
On the quick trip back to Earth, Ruth and Cal battle mutants and land the plane on the surface as the dying Exeter crashes the ship into the ocean. The water flares a bright neutrino green as credits roll.
Aside from the neutrino panacea, This Island Earth is exceptional for it's positive stance on nuclear power. Nine years after the nuclear ending of WWII, the film carefully avoids mentioning atomic weapons, choosing instead to build a cleaner, nuclear image (the uranium is used for shields, not weapons). And while the Metaluna mutant may be an allusion to genetic disfigurement, it's more likely that the film needed a bug-eyed monster to threaten the lovely Ruth instead of a subtle atomic warning to the viewers.