What we do know is that it was a third-party who managed to get the recording equipment in for the audio you hear here. Five minutes of it was played at the film's London premiere and the full 30-minute version will be in cluded on the DVD.

On the DVD, the real Mr Bronson talks about the prisons, the brawls, the protests, the riots and the thirty years of isolation; the fact he is no longer allowed windows or any communication with any other inmates. It's powerful stuff and sure to aggravate his prison guards.

The real Bronson is not allowed to see the film as he is still a category A prisoner, but he has apparently listened to the film and was very pleased with it, especially the performance of Tom Hardy who visited him in jail. For a man who back in 1974 was known as Michael Peterson and was determined to make a name for himself, a titular, feature-length movie is some coup.

Director Nicolas Winding Refn says about his new film, “It is Bronson’s unending thirst for celebrity that has kept in prison for so long.  And it was this particular aspect of his personality that we tried to capture in the film.”

If you didn't know about Bronson, you do now. And boy will he be happy about it.