Notorious K.I.D: My son Biggie by Voletta Wallace

Behind the larger-than-life protagonist who bestrides the film, the real hero of Notorious is Voletta Wallace, the gutsy single mother who battled to raise Christopher Wallace (later Notorious B.I.G) in the chaos of 1970s Brooklyn.

Wallace is portrayed by Angela Bassett as a strong and resourceful character who successfully battled two bouts of breast cancer as her wayward son was dropping out of school, dealing drugs, and talking of pursuing ambitions as a rap artist.

Wallace, now 56, is the keeper of her son's legacy. She worked as co-producer on Notorious, helping secure finance and working with writer Cheo Coker to chronicle her late son's colourful life and controversial death. "I made Notorious because I needed to put some things out there," she said this week. "Plenty has been said about him before. But I felt I wanted to put my story, because from what I knew about Christopher, his life was encouraging, and something people could learn from.

"During our research, I did learn plenty of things that shocked me, though. For example, I'd never known he started selling drugs so young. In my eyes, he used to be very innocent. I guess you could call me naive."

Her son was a "grade A student", she says, who had an "incredible memory", was outgoing and top of his class at his private Roman Catholic school. However, he became a boisterous teenager who transferred to a gritty public high school, at his own request, before quitting for a career in hip-hop.

"At first, I detested the idea of him going into rap music," she recalls. "I thought he could do so much more. Of course, now I hope men and women can learn something from what he achieved, and see how he made something of his life.

"Going over his career was painful for me. But I believe there's a lesson to be learnt from it, and I hope that's what Notorious shows people: that if you have talent, and work hard, and work at it. Then good can come of it."

Fittingly, given its title, the makers of the film found themselves facing a series of Biggie-sized controversies when the film opened in the US last month. First, four men were stabbed, leaving one critically injured, when a fight broke out in a Brooklyn nightclub that was holding an after-party to celebrate its New York premiere. Then police were called to cinemas in Texas and Ohio, when crowds of teenagers started riots – each involving an estimated 2,000 people – after being refused entry because of its "R" rating, which requires viewers under 17 to be accompanied by an adult. Finally, Wallace's former girlfriend Lil' Kim, played by Naturi Naughton, issued an angry statement complaining at her portrayal as a vulgar seductress who used her relationship with Notorious B.I.G to advance her professional ambitions.

Despite, or perhaps because of, the brouhaha, Notorious has been a box office smash, taking $23m in its opening weekend, despite being placed in just 1,600 cinemas by Fox Searchlight, the studio's specialist distributors. Its soundtrack reached No 4 in the charts.

Wallace, who runs the Christopher Wallace Memorial Foundation, which finances educational projects in America's inner cities, says its success has provided a fitting tribute to her late son.

"When my son died, he was about to live, he was looking forward to life. That's the tragedy of it, and it needed to be shown. He could have accomplished so much. He was planning a clothing line, a restaurant, a record label. He would have become one of America's greatest entrepreneurs. I believe that, I really do."