"Chi-Raq," a combination of Chicago and Iraq, is Spike Lee's latest film. Set in the violent neighborhoods of Chicago, women band together to abstain from sex to persuade their significant others to end gang violence. (  / Roadside Attractions)

With its titular city again making unsettling headlines this week, “Chi-Raq” arrives like an audacious, confounding, unabashedly sincere cry of the heart. Over the past few years, Spike Lee has been working on smaller canvases, experimenting with personal narratives (“Red Hook Summer”) or remaking other filmmakers’ work (“Da Sweet Blood of Jesus” and “Oldboy”). With “Chi-Raq” he’s boldly trying something new yet again, adapting the Aristophanes play “Lysistrata” into a contemporary parable set within the culture of guns and gangs on the South Side of Chicago. (The title refers to an unwelcome nickname the city has earned as local gun deaths have exceeded mortality rates in the Afghanistan and Iraq conflicts.)

Spoken almost entirely in verse, staged as a sometimes ungainly series of polemical set pieces, production numbers and declamatory interludes, “Chi-Raq” doesn’t fit neatly into any genre. It’s a satire stuffed into a musical tucked into a melodrama, fused together by Lee’s signature visual brio and Terence Blanchard’s elegant orchestral score. It’s a bit of a mess, but a bit of a masterpiece, too: Just when you think Lee has lost his grip on a movie that can’t decide what it is, he grabs you by the throat with the urgency, passion and instincts that have made him one of America’s great cinematic artists. (“Chi-Raq” was produced by Amazon Studios, a company owned by Jeff Bezos, who also owns The Washington Post.)

Teyonah Parris stars as Lysistrata in “Chi-Raq,” director Spike Lee’s adaptation of the Aristophanes play. (Parrish Lewis/Roadside Attractions)

One of Lee’s best moves with “Chi-Raq” was finding an electrifying actress to fill its central role: As Lysistrata, Teyonah Parris takes early command of the screen, when her character attends a performance of her boyfriend Chi-Raq Dupree (Nick Cannon), a rapper and gang leader of the Spartans. When his arch-rival Cyclops (Wesley Snipes) — leader of, what else, the Trojans — stages an attack onstage, and later sets fire to Chi-Raq’s house, Lysistrata takes shelter with a wise neighbor named Miss Helen, played by Angela Bassett. Together, the women hatch a plan — in part inspired by the 21st-century tactics of Liberian peace activist Leymah Gbowee — to withhold sex from their male partners until the men disavow gun violence. “Lock it up!” the women chant, vowing to “deny all rights of access or entrance” until the shooting stops.

In real life, Gbowee has observed that the Liberian sex strike was more effective in garnering media attention than changing behavior. For Lee, the conceit allows him to indulge in some of the same objectification and simplistic sexual politics that often have characterized his work. But it also enables him to take on an entire constellation of social and historical forces that have conditioned African American life, not just in hyper-violent Chicago but throughout the country. In a subplot involving a grieving mother played by Jennifer Hudson, Lee calls out the stop-snitching ethos and glamorization that attach to thug life. And in a fiery sermon delivered by John Cusack’s radical Catholic priest, he takes on gun laws, structural poverty, the NRA, the school-to-prison pipeline and mass incarceration that he hoarsely calls out as “the new Jim Crow.”

We haven’t even gotten to the part where a National Guard officer mounts a cannon dressed only in his Confederate flag-emblazoned skivvies.

Nick Cannon stars as Raq Dupree in “Chi-Raq.” (Parrish Lewis/Roadside Attractions)

Lee wrote “Chi-Raq” with Kevin Willmott, whose wildly imaginative and similarly uneven satire “C.S.A.: The Confederate States of America” recast political history as if the South had won the Civil War. Unleashed here, Willmot’s sensibility veers daringly, if occasionally unsteadily, between the stirring and the silly. There are a few corny, too-obvious moments, such as a simpering appearance by a character named Oedipus, and a neighborhood cafe conveniently called the Deus Ex Machina. But within the movie’s heightened theatricality and stylization, there are moments of inspired lunacy and outright brilliance: As Dolmedes, the one-man Greek chorus, Samuel L. Jackson provides a running commentary that is as sharply observant as it is profanely unprintable; and even though she’s given a role in which she’s unforgivably not asked to sing, Hudson conveys shattering depths of sorrow that Lee never loses sight of, even at his absurdist heights. (“Keep Loving Each Other,” reads one of several graffiti messages that serve as another kind of chorus.)

One of the most potent moments in “Chi-Raq” is when Lee quotes “The Great Train Robbery” to illustrate the dilemma of black communities caught between gangs and violent over-policing. He references other movies as well, including “Dr. Strangelove” and “Patton.” He also makes use of a few of his own signature flourishes, including his calling-card dolly shot. (“Chi-Raq” has been vibrantly photographed by Matthew Libatique.) The film is such a grab bag of images, moods and tones that, if you find Bassett’s showdown with a predatory insurance agent unconvincing, you can wait around for a cleverly choreographed dance set to the Chi-Lites during “Operation Slow Jam,” designed to weaken the women’s resolve.

The through-line of “Chi-Raq” is a sense of crisis that Lee refuses to reduce to binary causes, but interprets in terms of history, economics and psychology, as well as the personal, political and spiritual. It’s a lot to shoehorn into one movie, let alone one that traffics in the arcane narrative style of “Chi-Raq.” But Lee is propelled by righteous anger that can’t help but be infectious. Even at his most reckless, even outlandish, he’s on the side of the angels.

R. At area theaters. Contains strong sexual content including dialogue, nudity, strong language, some violence and drug use. 118 minutes.