Dr. Cal Meacham (Rex Reason) is a hunky pilot and scientist. Working for the government, he receives parts from a mysterious source. Assembling them, he finds that it is a giant video phone with lasers. The mysterious Exeter recruits Dr. Meacham for a special, super secret project. Boarding a pilotless airplane, he lands at a remote research facility/Shangri-La where many noted scientists run around like frightened rabbits.
But not Meacham, no sir. He's far too hunky macho for that. He takes charge of the situation and with the aid of The Professor and the requisite hottie, he learns that Exeter and his high-brow bunch are really aliens getting the humans to build ... well, enough spoiling. Suffice to say that the Metalunians need our help and are just too shy to ask.
Are the Metalunians evil or can they be trusted? Funny thing is, if Meacham doesn't get on that plane, nothing happens. No consequence to him or the Earth. The story ends there. In fact, little difference to ANY of the characters in the story. Oh, well. Sometimes a hero needs a scenario to be heroic. Rex, tired of acting, turned his back on Hollywood at age 32. He's still alive and does autograph sessions from time to time.
I watched this with my 13 year old and we both enjoyed it. I might see it again. Actually, we will because I plan on borrowing the MST3K movie (1996) which features it. I loved the series and my boy has never seen an episode. His final comment about This Island Earth is that the title is dumb. I agree. AMRU 3.5.