Purgatory: A "trial"

How many times in our lives have we, willingly or unwillingly, witnessed a crime, powerless to intervene?

Romeo Castellucci in Purgatory (2008), breaking with the stereotyped dramatic norms of his earlier work, places us in an apparently monotonous everyday situation. Nothing warns us of what is about to happen. We shall not see, but we shall experience violence, numbed and unable to react.

What is it that shocks us the most? Viewing the violence, or experiencing a violence unseen?