“The Leopard” turns 60 this year, and is stalking the IFC Theater on Sixth Avenue through the end of this week, in 4K restoration. If one is going to be its prey, get comfortable, as the film by Luchino Visconti and starring Burt Lancaster, Alain Delon, and Claudia Cardinale runs just shy of three hours. From  another world, it’s suited for this moment because it wonders how to conserve what’s good amid chaos.  

The film is an adaptation of a book of the same name, Il Gattopardo, published posthumously in 1958 by the 12th Duke of Parma and the last prince of Lampedusa, Giuseppe Tomasi di Lampedusa. Hobbled by early rejection, it won the Strega Prize for Italy’s best novel and now reigns as an undisputed classic. It imagines the life of one of Lampedusa’s ancestors just before the Risorgimento, the unification of Italy, in 1861.

The film was shot at Palermo and snagged the Palme d’Or at the 1963 Cannes Film Festival. Like the book, it was an acquired taste among critics, with some seeing it as ponderous and meandering. Time has been its ally, however. The director Martin Scorcese counts it among his 12 favorite films, and the British Film Institute rates it as the 57th best movie of all time.   

The movie followed close on the book’s heels. Lancaster is an aging aristocrat, Don Fabrizio Corbera, the Prince of Salina, navigating swirling cultural and political waters. The future is incarnated by his nephew Tancredi, played by Mr. Delon. He is pledged to Don Fabrizio’s goddaughter, Angelica Sedara, played by Ms. Cardinale. Angelica Sedara possesses in beauty and new wealth what she lacks in pedigree. This is a world where, in Antonio Gramsci’s phrase, the “old is dying and the new cannot be born.”

Mr. Delon’s Tancredi, played with a rake’s verve, personifies the new dispensation, trying his fortune with every faction, switching from forces loyal to the republican rebel, Giuseppe Maria Garibaldi, to those who serve the king. His marriage to Sedara rather than Don Fabrizio’s own daughter, Concetta, is a pragmatic coup but a blow to the ancient family’s prestige. A clan that claims descent from Roman emperors throws its lot in with the nouveau riche.     

The duke sees a universe toppling, with timeless feudalism giving way to the harsh energies of republicanism. The action is set in Sicily, a place that the celebrity chef Anthony Bourdain once summed as “It’s Italy, but it’s not.” Or, as “The Leopard” explains about Sicilians, “our sensuality is a hankering for oblivion, our shooting and knifing a hankering for death.” Even the “drugged sherbet” betrays a “voluptuous immobility.”

Visconti’s film captures Sicily’s sun-soaked milieu, its sun-baked expanses, and the hunt for shade. Characters constantly dab their foreheads with handkerchiefs, trying to staunch the flow of sweat. Also melting is the old, slow order of things. Don Fabrizio is a scion of a kingdom going the way of the dodo. He declines entreaties to enter politics. The result of the only plebiscite we see in the film is 512 to zero, an indication of corruption rather than constitutionalism.  

It is in this vortex that Don Fabrizio observes that “If we want things to stay as they are, things will have to change.” Mutability is the key to preservation, along with a keen awareness of loss. The film’s title is sourced to an observation by Don Fabrizio that “We were the Leopards, the Lions; those who’ll take our place will be little jackals, hyenas; and the whole lot of us, Leopards, jackals, and sheep, we’ll all go on thinking ourselves the salt of the earth.”

The film begins with the members of the prince’s household fingering the rosary, and it ends with a ballroom scene where all the upper crust Palermitanos gather to eat crustaceans and dance the waltz and the mazurka. Don Fabrizio is of the scene but not completely in it, haunted by a present that is marbled with nostalgia. He is not a traitor to his class so much as a Cassandra who can’t be bothered to scream. There is nothing new under the Sicilian, or our, sun.