British actor Tom Hardy is braver than most - he risked upsetting the U.K.'s most violent prisoner by comparing him to a member of camp 1970s band Village People.
The RocknRolla star plays notorious convict Charles Bronson in a movie biopic of the career criminal's life, titled simply Bronson.
To prepare for the role, he visited the crazed armed robber in jail for a series of "interviews" so he could study Bronson's mannerisms.
And their first meeting almost turned ugly - when the actor joked that the crook's handlebar moustache made him look like a singer with the YMCA hitmakers.
Hardy says, "He was concerned that I wasn't heavy enough to play him. So obviously it was, 'What you gonna do about the press-ups, Tom? What you gonna do about the moustache?'. I was like, 'Well, you know, I don't think I'm going to go with it Charlie.' (He said) 'You f**king what? This is the most famous 'tache in the penal system!' I said, 'Yeah, but it's a bit Village People isn't it mate?'
"He went, 'Whoa! YMCA!... Seriously, what you gonna do about the 'tache?'. So I got the 'tache!"
Bronson was jailed for armed robbery in 1974 and has stayed behind bars ever since due to a string of assaults on fellow inmates and prison guards. He once led an infamous protest on the roof of a prison, and even took jail staff hostage.