The sober real-life concerns at the heart of “Chi-Raq” aren’t the sort of issues Nick Cannon usually deals with. The cheerful actor started his career with light television sketch comedy in Nickelodeon’s “All That” and MTV’s “Wild ‘n Out” — so starring as a rough, gun waving gangbanger isn’t exactly typecasting for Cannon.

Adapted by Spike Lee from the satirical antiwar Greek classic “Lysistrata,” the film’s Chicago universe is senselessly violent, sexist and corrupt. The movie’s title is the nickname of the city’s war-zone-like South Side. Still, the role was irresistible, Cannon said by phone from New York City.

“They always say that comedians have the most darkness in them, and this is a satire of what’s going on in society right now,” he said. “It has such a serious tone with so much weight and substance about what’s actually going on in the South Side of Chicago that I was able to relate and connect with the authenticity of the community.”

While the film’s branches of larger-than-life parody and bawdy farce also attracted him, its biggest appeal was the opportunity to play a leading role for Lee after years of missed opportunities.

“Luckily, the great Spike Lee, who is to me one of our greatest filmmakers of all time, believed in me and knew I could bring it to pass,” Cannon said. “I’ve always aspired to be a character actor ­­— to jump into other characters and disappear is what an actor dreams of.

“Once I saw how he was going to take it on artistically — wow, I was even more excited. It’s so courageous and potent and so timely that I was game.”

While comedians often like to improvise and be funny on the fly, delivering Lee’s sharply crafted dialogue word for word “was a real great blessing. When you have someone like Spike at the helm, I could just relax.”

Moving far from his sideline as an R&B hitmaker with novelty comedy albums like “White People Party Music,” Cannon created and performed the film’s stop-the-violence theme song “Pray 4 My City.” He hopes it will have an impact beyond “Chi-Raq’s” soundtrack.

Like the film, he said, his track is about “understanding humanity. A life is a life whether it’s in our own community or globally. People need to pay attention and wake up. Put together responsible action and take responsibility for our neighborhoods. Recondition the mind-set and uplift.”

One of “Chi-Raq’s” themes is that men view power as a path upward while women see it as a tool to protect the vulnerable. “I love that idea. I believe that women are the most powerful species on the planet. I know quite a few,” he laughed.

“The story line is not only about the power of their sexuality,” as Chicago women start a sex strike to persuade their men to end their gang war, “but also the power to be so nurturing, to be such amazing spirits,” he said. “It’s truly remarkable when you see everything our mothers, daughters and sisters go through daily and still hold their heads high. And control the male species whenever they need to.”

While one of “Chi-Raq’s” showcase scenes is a thunderous political speech delivered by John Cusack’s Father Mike Corridan (modeled after Chicago priest the Rev. Michael Pfleger), lectures and love boycotts “both deliver a synonymous message. We need to hear those things, and when we can go to a safe haven like a church or community center and be motivated and preached to at those times, it definitely makes you step back and think,” Cannon said. “If you get down to the core, and even what ‘Lysistrata’ was about 2,000 years ago, it’s all about focusing on humanity.”