There’s lots of big ideas to convey about the headlines plaguing us today in Spike Lee’s fever dream fable Chi-Raq (B). Although overstuffed with plot and prose, it’s a powerful entreaty to end the violence dominating inner-city America and in Chicago in particular. Lee’s unconventional narrative is a modern-day adaptation of Lysistrata, complete with rival gangs, rhyming lines, a charming narrator (Samuel L. Jackson) and a formidable heroine, played with fierce majesty and commitment by Teyonah Parris. Nick Cannon is cold and effective and near-unrecognizable as a lead gang member in a plot about women abstaining from sex as the ultimate way to get the men of their community to wake up and restore civility. Lee’s film suffers from an avalanche of gonzo notions, many of them quite brilliant and some of them self-indulgent detours that could have used some judicious editing. But ultimately it’s a shock to the system and a vivid reminder of the political power he has as a filmmaker. It’s vivid and sometimes makes you livid and is an important take on society today.