When tree-tall aliens, called Kanamits, from another planet visit the earth claiming to be able to wipe out everything that ails our planet and its inhabitants, they are greeted with guarded optimism. When they succeed in doing just that, any suspicion that may have existed is erased. When they first land, they leave behind a book in their own language, and when the title is deciphered, it reads "To Serve Man". These guys are heaven sent, end of story!
The story's main earth characters are scientists Susan Cummings and Michael Chambers, the latter who guides us through the story in flashback while on the Kanamit ship. When these space angels start allowing excursions to their own planet, Chambers, feeling there's nothing much more to do since history is at an end and the earth is now a paradise, decides to take one. Cummings, however, is not content with leaving the rest of the book alone, and painstakingly deciphers it. What she finds is that the word "Man" in the title is gramatically the direct object, and it implies a third party, an indirect object. That is, man is to be served AS A DISH. Her warnings to Chambers are too late, so, breaking the fourth wall, he looks into the camera to ask what we will do, resigning himself to his own fate, and that of the planet.
Some sci-fi stories, including a few on TZ, see space aliens as messiahs. Episodes "The Gift" and "Valley of the Shadow" are two examples, as well as movies like "The Day the Earth Stood Still" and "Cocoon". Then there are others, like the story "War of the Worlds" and the 80s TV series "V", which has been remade and is currently airing, which, like "To Serve Man", remind us that while we should not be unduly suspicious of "visitors", we should not be unduly trusting of them either.