A science fiction author, Robert Heinlein, famously stated that “every generation thinks it invented sex, and every generation is wrong.” Something similar could be said of “The Invasion of the Body Snatchers” (1956). Director Don Siegel’s sci-fi parable about conformity and paranoia has seen three remakes — there is, apparently, another in development — and its tendrils have spread into many byways of popular culture. Every passing decade, it seems, needs to redefine body-snatching, but none have been as good as the original.

Kino Lorber is set to release a restored version of the Siegel film on Blu-ray. The package includes a host of extras, such as an audio commentary featuring “Invasion” stars Kevin McCarthy and Dana Wynter chatting with the director of “Gremlins,” Joe Dante. There are essays by B-movie connoisseurs Richard Harland Smith, Steve Mitchell, and Jason A. Ney, as well as a featurette, “The Stranger in Your Lover’s Eyes.” The latter is a documentary by Elijah Drenner outlining the movie’s production. Its text was culled from Siegel’s autobiography and is read by his son, actor and director Kristoffer Tabori.

Even those who don’t have a passion for vintage science fiction should be able to infer the relationship between the title of Mr. Drenner’s short film and the picture under discussion. The basic storyline about a world just off-kilter has been absorbed into the body politic: The mere mention of “pod people” will have Mr. and Mrs. America nodding in acknowledgement. When producer Walter Wanger, Siegel, and novelist Jack Finney — whose book, “The Body Snatcher,” (1955) was the film’s basis — started on this venture, they could have had no idea of its staying power.

“They Come From Another World” — one of the working titles for the picture — was a low-budget affair made on the quick. Although McCarthy had been nominated for an Oscar for his portrayal of Biff Loman in László Benedek’s “Death of a Salesman” (1951), he wasn’t a star property: McCarthy was toward the bottom of Wanger’s wish list as lead. Wynter had been pegged by the Golden Globes as Most Promising Newcomer in 1955, but she wasn’t a bankable commodity. Because the bottom line couldn’t coast on celebrity, Wanger and Siegel opted for invention born of necessity. 

That, and conviction. The actors are pitch perfect in their relative anonymity. The secondary players — especially King Donovan, Larry Gates, and Virginia Christine — are as rooted as McCarthy’s Dr. Miles Bennell and Wynter’s Becky Driscoll are emblematic of an idealized middle America. Remakes of the film have opted for flashier locales — San Francisco, Washington, D.C., like that — but it’s the Rockwellian enclave of the invented city of Santa Mira that hits home: Its generic character only underlines how pernicious change can be.

What to make of Uncle Ira, who dutifully mows the lawn as usual and yet is something less or, at least, something different than what he’s always been? Reams of explication have been written about the “true” meaning of this picture, particularly given the film’s time frame. The Korean War, the McCarthy hearings, the Communist menace, the atom bomb — the various people involved in the picture denied the inclusion of political undercurrents. 

Siegel made a point of “not want[ing] to preach.” Which isn’t to say that art forms don’t absorb the tensions inherent to the times in which they are created. 

There are significant reasons why “Invasion of the Body Snatchers” holds up better than the majority of creature features of the time. Chief among them is the nature of the creatures themselves. No oversized rubber suits or rickety special effects here: The monsters are those we see in the mirror, albeit bereft of soul, agency, and the capacity for love. 

As another icon of the 1950s, Walt Kelly’s classic comic strip “Pogo,” would have it: “We have met the enemy and he is us.” The follies of humankind are forever eternal and so, too, is the cautionary tale told by “Invasion of the Body Snatchers.”