For Pariah, imagine a sparse 19th century science-laboratory: a table bearing a microscope, some exquisite old-fashioned bottles, and a small wooden chest. Mr X, played with dusty assertiveness by Lawrence Werber, is a scientist who once killed a man by accident - but escaped imprisonment. John Ogilvie is the ambiguously meek Mr Y, who has suffered two years of humiliation behind bars for forgery - and the result is an uncannily Hitchcock-like argument about morality and intellectual superiority.