There is an article by Bryan Appleyard in the dead tree edition of today's Sunday Times Culture magazine, about the play and includes a brief interview with Joseph, who apparently is in the process of losing 2 stone in weight for the role.
"I have to look the part, as there does seem to be an implicit understanding in the play of how long he has been in these terrible places. There' is a kind of addiction to matyrdom in him that has quite a bit of glamour in it. It seems quite important to him that his name is known in the west."

 

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