Searchlight’s “Nightmare Alley” takes place mostly in 1939-41, but its sensibility is contemporary. It’s a time-capsule movie: If future generations want to know what life was like in the 21st century, tell them to see this film.

“Nightmare,” written by Guillermo Del Toro (who directs) and Kim Morgan, depicts a world of liars and charlatans who manipulate the truth to gain wealth and/or power. And the general public is surprisingly gullible. As Lilith (Cate Blanchett) says to Stan (Bradley Cooper), “You don’t fool people, Stan, they fool themselves.”

Del Toro tells Variety, “We are in a moment of great anxiety, post-discourse, post-truth, almost as if we, as a society, are going through a psychotic episode. Everybody curates the reality of the world, every piece of information, to fit their own ‘truth. And I mean everybody; this is not about a particular person or party. This is a moment when we either recuperate or destroy each other.”

In the film, Stan tells good-girl Molly (Rooney Mara), “I’m afraid every day of my life.” He also says, “Sometimes you don’t see lines until you cross them.”

Del Toro says, “For me, that encapsulates the anxiety that is in the air — the need for a tacit agreement on truth and lies, which has evaporated. That anxiety is the reason we wanted to do the movie.”

The plot closely follows William Lindsay Gresham’s 1946 novel, which was filmed in a 1947 version starring Tyrone Power.

Drifter Stan joins a carnival, whose attractions include mind-reader Zeena, “freaks” like Dogboy and Birdgirl, and a geek, who bites the head off a chicken (“Is he man or is he beast?” the carnival barker exclaims). In this world, performers and audience share the fun possibility that it’s all illusion.

Stan then moves to the city and becomes a nightclub mentalist, encountering more deceptive people. “Nightmare Alley” is noir and del Toro says, “America invented noir, because it’s a handy metaphor or parable for when the dialogue itself breaks.

“Noir is a genre that reflects the time it’s made in,” he adds. There were 1940s noir (“Double Indemnity”), Cold War noir (“Kiss Me Deadly”), post-Vietnam (“Chinatown”) and neo-noir in the ’80s, reflecting the decade’s greed (“Body Heat”).

Del Toro’s film includes spectacular artisan work that is hypnotic, seductive and Oscar-worthy. He says of his behind-the-camera team, “We wanted to reflect the nightmare alley we’re in. When I’m working with the departments, I write them a biography of the characters, and they tell me how they will articulate this through their craft.”

Traveling carnivals and nightclub mentalists were familiar to readers and moviegoers in the 1940s. And Variety’s Archives show that Stan made a smart move by exiting carny life. The Depression ravaged the carnival business. In 1933, the newspaper reported that West Coast sideshows had dwindled from a dozen to only three, within a six-year period.

Variety regularly reported on carny and nightclub life and people who worked there apparently appreciated it. Gresham’s novel including this profoundly important sentence about the sideshow mindreader: “Zeena filled an armchair beside the window, fanning herself gently with a copy of Variety.”

The sideshow charlatan may not have been completely honest, but at least she had good taste.