In August 1968, with two self-financed films already to his credit, 45-year-old author Norman Mailer used money he earned from selling his shares in the Village Voice to assemble a cast and crew and descend on East Hampton, Long Island, for a four-day film shoot. The resulting movie, “Maidstone,” will kick off the Film Society of Lincoln Center and Anthology Film Archives’ tribute to Mr. Mailer’s film legacy in an ultra-rare screening Sunday night at the Walter Reade Theater. Mr. Mailer will be on hand to discuss the production and impact of “Maidstone,” as well as his 1987 film “Tough Guys Don’t Dance.”

When “Maidstone” went before the cameras, Martin Luther King and Robert Kennedy were barely in the ground and Andy Warhol was in the hospital with the gunshot wounds he received from a deranged hanger-on, Valerie Solanas. The Democratic National Convention in Chicago was turning into a street fight, and newspaper headlines trumpeted all manner of social upheaval threatening or potentially transforming the land of the free.

Mr. Mailer’s film would enthusiastically embrace 1968’s American media frenzy zeitgeist of assassination, racial strife, sexual freedom, celebrity worship, and highly contentious presidential politics.

It would also embrace a concurrent revolution in filmmaking. The vanguard cinéma vérité nonfiction films of the Maysles Brothers and especially D.A. Pennebaker had replaced, Mr. Mailer wrote, “the stodgy, unhappy catatonia of the old documentary.” Using five camera teams headed by Mr. Pennebaker, his colleague Richard Leacock, and three other documentary cameramen, Mr. Mailer sought to explore his own notion that “cinéma vérité might also be used to photograph feature-length movies that told imaginary stories.”

During the course of their four days together in East Hampton, a cast, led by Mr. Mailer himself, would ad-lib and interact as naturally as his film’s loose scenario and physical shooting circumstances permitted.

“Right now the film does not exist as a plot, only as a presence,” the director and star told his assembled company as shooting began. What plot “Maidstone” possesses is tied to a film-within-a-film helmed by Norman T. Kingsley, a film director and presidential hopeful played by Mr. Mailer (born Norman Kingsley Mailer). Kingsley may or may not be the object of an assassination conspiracy undertaken by a shadowy organization called PAX, C (to my knowledge the only initialed villainous movie cabal to have a comma in its name), or possibly by members of Kingsley’s own retinue, who staff and operate the Cash Box, a male prostitute brothel and “Belle Du Jour” burlesque.

The production presence of “Maidstone” eventually steamrolled over the homes and lawns of such esteemed East Enders as Grove Press editor Barney Rosset , the artist and collector Alphonso Ossorio, and Robert David Lion Gardiner. Its cast, led by Rip Torn as Kingsley’s brother Raoul O’Houlihan Rey, would swell to include the poet Michael McClure, light heavyweight champion Josés Torres, Warhol superstar Ultra Violet, future “Fantasy Island” greeter Hervé Villechaize, and two of Mr. Mailer’s ex-wives.

Press accounts at the time gleefully reported every detail of outrageous (for East Hampton) and booze-fueled couplings, confrontations, and carryings-on taking place on both sides of the camera. Pressed to uninhibitedly improvise, many of the cast members turned to alcohol to loosen up, and more than a few scenes embody the ugly, vaguely malevolent confusion of large parties in which too many people get too drunk for too long. The film’s labored casting-couch overtures and resulting sex scenes often have the feel of a feature-length midlife crisis.

“In an improvised film,” Sally Beauman wrote in her New York Magazine article about the “Maidstone” shoot, “the most assertive personality gets the largest part.” Among the starlets, socialites, writers, and actors all struggling to engage one another onscreen, only Messrs. Mailer and Torn are able to get in touch with the necessary personal demons to mold drama out of the clumsy excess and sybaritic chaos of the film’s production and its jumbled, jumpcut intensive final edit. Their climactic physical skirmish is shocking, petty, intimate, embarrassing, and inevitable all at once.

“The picture doesn’t make sense without this,” Mr. Torn (or was it Raoul Rey?) says in the aftermath of the wild-eyed attack that closes the film, and he, or his character, or Mr. Mailer, by including the excruciating and fascinating scene in the final cut, is absolutely right.

Anyone who has ever taken an acting class knows the peculiar self-defeating desperation that results from unstructured improvisation. A drama teacher I know calls such anxious, forced, and dramatically inert non-moments “weird, paranoid scenes.” “Maidstone” has enough awkward, unscripted actor-to-actor anxiety for a dozen movies. But the year of the Chicago Seven, the Tet Offensive, and My Lai was a weird, paranoid time.

Mr. Mailer’s “Maidstone” is not the “beautiful, tasteful, resonant, touching, evocative picture,” that its director and star aspired to when he addressed his troops on day one in East Hampton. Nevertheless it remains an audacious and seminal entry in its creator’s compelling body of print and film work and an invaluable, though dented and misshapen, time capsule of the year that spawned it.