Midway through “Django Unchained,” the freed slave of the title (Jamie Foxx) enters an antebellum bar and sidles up to a patron played by Franco Nero.

The ageless Italian actor, looking sharp in a duster coat and white gloves, found fame in the 1966 spaghetti Western “Django.”

The encounter is inserted by writer/director Quentin Tarantino to honor this namesake cult hero. But it’s clumsy. Foxx and Nero don’t connect. They’re going through polite motions, as if on an awkward blind date. And their exchange does nothing to move the plot forward.

The scene is emblematic of Tarantino’s new effort.

Coming off 2009’s brilliant “Inglourious Basterds,” Tarantino hopes to revamp the Western as successfully as he did the war film. Instead, “Django Unchained” becomes an epic mess. A cool premise is routinely thwarted by a capricious, unsatisfying script.

It’s also a project infatuated with cruelty and degradation, all presented with a cutesy wink-and-a-nod. It wants to be “The Wild Bunch” but has more in common with “I Spit on Your Grave.” Fortunately, Tarantino lays on just enough of his signature flamboyance to keep it watchable.

Foxx stars as Django, a slave in 1850s Texas rescued during the film’s formulaic opening by Dr. King Schultz (Christoph Waltz), a German dentist-turned-bounty hunter. Because Django can identify the fugitive Brittle brothers, King makes him a deal: If Django helps capture the quarries — dead or alive — King will assist in rescuing his slave wife, Broomhilda (Kerry Washington), who has been sold to another plantation.

Sound like a great setup? It is, except that story is resolved within the first 45 minutes, when improbable sharpshooter Django unleashes his revenge on all three Brittles. It’s the classic error of the screenwriter getting too tricky for his own good (“No one will see that coming!”). True, but now what do you do for the next hour and a half?

The answer is to add enough wandering around to rival “The Hobbit.” Since the give-and-take dynamic of the duo’s relationship is dismantled by Tarantino’s early climax, King is compelled to help Django save Broomhilda because … well, just because.

The men head to a Mississippi plantation owned by malicious Calvin Candie (Leonardo DiCaprio, a solid performance in service to a one-note character). Candie runs a side business in Mandingo slave fighting. For the residents of “Candyland,” Django is a revelation: the first black man they’ve ever seen riding a horse. The heroes hope to con their way into freeing Broomhilda by feigning financial interest in the fight trade.

Candie responds, “You had my curiosity. But now you have my attention.”

By the time the movie finally arrives at the penultimate showdown, it’s shocking to see things resolve with a Peckinpah-style shootout. At that point the audience has been lulled into a catatonic state from the nonstop speechifying.

Two key performances salvage “Django Unchained.” Waltz, the Oscar winner from “Basterds,” emerges as the most appealing figure. His scholarly, “fancy pants” mercenary proves a master of talking his way into and out of trouble.

Also noteworthy is Tarantino regular Samuel L. Jackson, initially unrecognizable as the head house slave and unlikely confidant of Candie. He’s arguably the canniest individual in the drama — certainly a lot more intriguing than Django, who’s armed with only surface motivations. Tarantino composed the lead role for Will Smith, and it might have suited the star better. Foxx is an artist of immense talent but limited likability.

That also describes “Django Unchained.” The movie parades the full scope of Tarantino’s cinematic sorcery. Yet it’s too grueling to enjoy and too sloppy to respect.

Rated R for strong graphic violence throughout, a vicious fight, language and some nudity.

SEE THE INSPIRATION

Quentin Tarantino’s biggest influences for “Django Unchained” were not movies about American slavery but the spaghetti Westerns of Italian director Sergio Corbucci — especially “Django,” the source of Tarantino’s title character.

You can watch the 1966 Italian original starting Friday at the Tivoli Cinemas in Westport. Franco Nero (who gets a cameo in Tarantino’s film) stars as the loner who confronts a town of bandits. Details at tivolikc.com.

WHAT OTHERS ARE SAYING

•  David Germain, The Associated Press: “Granted, there’s something gleefully satisfying in watching evil people get what they have coming. But ‘Django Unchained’ is Tarantino at his most puerile and least inventive, the premise offering little more than cold, nasty revenge and barrels of squishing, squirting blood.”

•  Kyle Smith, New York Post: “ ‘Django Unchained’ might have been a revelation in 2005. But after Quentin Tarantino and others have spent years spoofing ’60s and ’70s genre movies, this mock spaghetti Western tastes like it came out of the microwave.”

•  Cary Darling, Fort Worth Star-Telegram: “Too bad there isn’t a better movie to go along with all the flamethrowing bravado.”