A car uncouples from a train, and curiously overalled children divert it to an isolated, mountainous country named Gudavia, a land where no trains ever come. The only two passengers on the train car, a boorish American and a stuffy Brit, are apprehended and thrown into a dungeon-like prison for being spies. Meanwhile, scientists in satin jumpsuits armed with an enormous laser gun scientifically impregnate human subjects dressed in odd military garb with electricity, turning them into idiots.
The two men are abruptly released, but they cannot leave the country because Gudavia's sole automobile is being used for official Gudavian business out of the country, which sounds fine. The Brit attempts to send a telegram, but it can't be sent because telegrams are only sent on special occasions. A young girl plays the piano as an oddly Aryan young man scowls.
Suddenly, there is a hubbub in the streets, and an old dude says, "In the end, the murdering will cease", because of course he does, and a guy with an extravagant hat chalks it all up to hysteria. In spite of the hubbub, the hysteria, and the murdering, the Brit wonders aloud about identity of his milliner. Somnambulant figures sneak up on the Brit, and they scatter after someone blows a whistle.
The pair meets up with a scientist with a double identity. This mysterious scientist pulled a disappearing act some time ago due to some sort of political thing (hint-hint, nudge-nudge), and he says some stuff about gamma rays. They then meet a Frau, who has children making monster masks for an upcoming festival, and there's almost nothing sinister about that at all.
Some stuff happens. The Brit chases a boy and falls in some water, the zombie guys throw rocks, a mule makes an appearance, and several people fall off a cliff.
The carnival that is certainly not a special occasion and that was forbidden to happen happens, and it's pretty freaked out, which means it's pretty cool, and the festival-goers wear giant monster heads, which I'm always a big fan of. Don't worry, since it's not too bad it only lasts a couple of minutes.
The Gamma People is a comic thriller, and it isn't particularly comic or thrilling.