“After Hours” approaches the notion of pure filmmaking; it’s a nearly flawless example of — itself. It lacks, as nearly as I can determine, a lesson or message, and is content to show the hero facing a series of interlocking challenges to his safety and sanity. It is “The Perils of Pauline” told boldly and well.

Critics have called it “Kafkaesque” almost as a reflex, but that is a descriptive term, not an explanatory one. Is the film a cautionary tale about life in the city? To what purpose? New York may offer a variety of strange people awake after midnight, but they seldom find themselves intertwined in a bizarre series of coincidences, all focused on the same individual. You’re not paranoid if people really are plotting against you, but strangers do not plot against you to make you paranoid. The film has been described as dream logic, but it might as well be called screwball logic; apart from the nightmarish and bizarre nature of his experiences, what happens to Paul Hackett is like what happens to Buster Keaton: just one damned thing after another.

It was the first film of Scorsese what would become his long collaboration with German cinematographer Michael Ballhaus, who had worked with Fassbinder and therefore knew all about low budgets, fast shooting schedules and passionate directors. It was shot entirely at night, sometimes with on-the-spot improvisation of camera movements, as in the famous shot where Paul Hackett (Dunne), the hero, rings the bell of Kiki Bridges (Linda Fiorentino) and she throws down her keys, and Scorsese uses a POV shot of the keys dropping toward Paul.

Another device was to offhandedly suggest alarming possibilities about characters, as when Kiki describes burns, and Paul finds a graphic medical textbook about burn victims in the bedroom of Marcy (Rosanna Arquette), the girl he has gone to meet at Kiki’s apartment. Are the burns accidental or deliberate? The possibility is there, because Kiki is into sadomasochism. Trying to find a shared conversational topic, Paul tells Marcy the story of the time he was a little boy in the hospital and was left for a time in the burn unit, but blindfolded and warned not to remove the blindfold. He did, and what he saw horrified him. Strange, that entering the lives of two women obsessed with burns, he would have his own burn story, but coincidence and synchronicity are the engines of the plot.

“After Hours” could be called a “hypertext” film, in which disparate elements of the plot are associated in an occult way. In “After Hours,” such elements as a suicide, a method of sculpture, a plaster of Paris bagel, a $20 bill and a string of burglaries all reveal connections that only exist because Paul’s adventures link them. This generates the film’s sinister undertone, as in a scene where he tries to explain all the things that have befallen him, and fails, perhaps because they sound too absurd even to him. One thing many viewers of the film have reported is the high (some say almost unpleasant) level of suspense in “After Hours,” which is technically a comedy but plays like a satanic version of the classic Hitchcock plot formula, the Innocent Man Wrongly Accused.

With different filmmakers and other actors, the film might have played more safely. But there is an intensity and drive in Scorsese’s direction that gives it desperation; it really seems to matter that this devastated hero struggle on and survive.

In “After Hours,” each new person Paul meets promises that they will take care of him, make him happy, lend him money, give him a place to stay, let him use the phone, trust him with their keys, drive him home – and every offer of mercy turns into an unanticipated danger. The film could be read as an emotional autobiography of that period in Scorsese’s life. The director said he began filming without an ending. IMDb claims, “One idea that made it to the storyboard stage had Paul crawling into June’s womb to hide from the angry mob, with June (Verna Bloom, the lonely woman in the bar) giving ‘birth’ to him on the West Side Highway.” An ending Scorsese actually filmed had Paul still trapped inside the sculpture as the truck driven by the burglars (Cheech and Chong) roared away. Scorsese said he showed that version to his father, who was angry: “You can’t let him die!” And so he does, although after Paul returns to the office, close examination of the very final credit shots show that he has disappeared from his desk.