In its concentration of interest upon the protagonists, Macbeth can be
seen as Shakespeare's experiment in unity of focus, whose chief appeal
arises from the struggles of the central characters with each other and
with the infernal powers that inspire or govern them. Over the
centuries, the vision of directors like Welles, Nunn and Polanski, as
well as the eloquent talents of actors like Garrick, Siddons, Olivier
and McKellen have contributed to the central debate of the play: Who or
what is culpable? Bernice W. Kliman, in her analysis of Macbeth in
performance, examines major productions of the play on both stage and
screen, thereby inviting the reader to contemplate directors' and
actors' choices for what is arguably Shakespeare's most compelling play.