Chi-Raq

Where is the most dangerous place in the world to be an American? It's not Iraq or Afghanistan. This year alone, 4,085 people have been shot in the city of Chicago, 660 of them fatally.

Spike Lee's Chi-Raq arrives on screens amid a storm of protest from the city's mayor, Rahm Emanuel, who has complained about the title and the impression it gives of his city ("I'm not the one pulling the trigger," Lee responded, adding that residents welcomed him during the filming process). It's no surprise that a subject like this would see passions run high, the more so because this isn't just another worthy documentary destined to preach only to the converted. It isn't an easily dismissed blockbuster either; its blend of sex, comedy, art and bleak observation will get under viewers' skin.

It has been 2,400 years since Lysistrata was first staged. During that time there have been no shortage of updates and adaptations, but it fits remarkably well into this new context, even some of the names having travelled by circuitous routes so that they sound natural. Its heroine (Teyonah Parris) is tall and slender with big hair and very short shorts - probably not what Aristophanes had in mind - but she gets her message across as well as ever, inspired not by the legend he reworked but by the 2003 sex strike led by Leymah Gbowee which was instrumental in bringing an end to 14 years of civil war. Can the black men killing each other in Chicago ("Nobody says gang any more. It's organisation.") be persuaded to stop if the alternative is not getting laid?

Though not entirely successful, Lee's adaptation certainly has balls. Rather than shifting into naturalistic dialogue, he uses rap-style rhymes to deliver most of the verbiage. Not every actor pulls it off but it works very effectively to connect two worlds, and at its best, it's beautiful. Samuel L Jackson is on fine form as the chorus, wearing a series of fabulous suits, his own film history pointing up the character of reconciliation. Meanwhile Angela Basset, in a supporting role as a bereaved mother, is raw and fierce, shredding the cheery comedy mood every time she speaks, and Lee knows exactly how to deploy her.

If you want to preach, you might as well incorporate a preacher. John Cusack plays the white guy who chose to move into the slums to live like Jesus did, and who gives voice to underlying messages about gun violence and the consequences of pervasive racism. The grief of many of the women over the recent death of an 11-year-old girl reminds us what's at stake, putting a human face on all that loss. At times, especially in the latter part of the film, the message gets too heavy handed, Terence Blanchard's score swollen with sentiment, but this was always going to be a difficult balancing act. Lee is at his surest in scenes of pure comedy, with Lysistrata's followers' adventures in an army barracks crude but entertaining. If one wants people to listen, one first has to seduce them.

This being Lee's work, there's an acknowledgement that not everybody needs cross-sex cooperation in order to have a good time in bed, and a slight but interesting testing of the boundaries of outlaw masculinity. There's also effective use made of visible disability and the impossibility of telling at a glance which kind of combat has cost young men their limbs. It's an important acknowledgement of the other costs of violence in a context where, too often, all anyone pays attention to is whether someone's dead or not.

Parris works well in the central role, balancing necessary boldness with the disconcerted look of someone who had a single bright idea and didn't expect it to make her an international celebrity. Opposite her, Nick Cannon bears the name of the film as the rapper who is the first to be denied his desires and the last to surrender, caught up in his own romantic interpretation of his city's bloody business. Wesley Snipes turns in one of his better performances as Cyclops, Chi-Raq's rival, with a couple of cute nods back to Aristophanes; and there's a poignant appearance by Jennifer Hudson, who lost three of her own family members in a shooting in 2008. But who now remembers the Peleponnesians?