I WOULD GUESS that almost everybody has a question they’d like to ask Mike Tyson. Did he rape Desiree Washington? What made him chew Evander Holyfield’s ear? What the hell is that tattoo of Mao Zedong doing on his bicep?

Perched tensely on a sofa, his crisply ironed shirt carrying a few remains of breakfast, the former heavyweight champion offers answers to all these questions in this curious new documentary from James Toback.

Not everybody will approve of those responses. When asked about the rape conviction, he furrows his brow. He is, he claims in a trembling voice, not guilty of “raping that wretched swine”. He blacked out during the Holyfield fight. Hey, everyone’s into Mao these days.

Still, despite apparent moments of self-deception, Tyson does make a genuine effort to engage with the most troubling and controversial incidents in his eventful life. Raised in a rough area of Brooklyn, Mike was rescued from a career in petty crime by Gus D’Amato, the great boxing manager, and moulded into the scariest heavyweight in history.

The most moving sections of the film are those in which Tyson – so psychologically contorted by grief he can barely speak – describes his feelings on hearing of D’Amato’s death. Nobody since has had the authority to save Tyson from his more unlovely instincts.

So the film is certainly of interest. This is by far the most comprehensive interview Tyson has yet given, and Toback makes sure to probe into all the darkest corners. It is cheering to note how much respect the boxer show for those he once fought. Lennox Lewis remains “a friend”. After explaining that he was in bad shape when he fell to Buster Douglas, he acknowledges his vanquisher’s achievement. The film underlines how foolish it is to define any man by his worst deeds.

Ninety minutes is, however, a long time to spend in the company of a man with such limited conversational skills. A few archive sequences aside, the film is taken up with Tyson's talking head and, with the best will in the world, nobody is going to mistake his rhetorical style for that of Muhammad Ali. Don't go in expecting When We Were Kings.