The Children of Spider County, directed by Leonard Horn.
Four brilliant young men in key fields have vanished. All were born in Spider County and share a strange early history. A federal agent suspects interference from planet Eros in the Krell (!) galaxy. He's going to check on a fifth young man, still at home but jailed for murder.
It's a good premise, similar to John Wyndham's The Midwich Cuckoos, filmed as Village of the Damned (1960), but this is a stiff reading of the story, lacking the thrills and sense of wonder we expect from the series.
One imaginative effect: when the alien exerts his mental powers we see strips of cloud passing across the screen. The characters in the program see them, too.
Familiar faces: Kent Smith (It Crawled Out of the Woodwork), Dabbs Greer, John Milford.
Photographed by Kenneth Peach, the first of his 25 episodes for the series. He will be the most common cinematographer from this point forward.
No commentary track on the Blu-ray.