I’m a big fan of genre cinema.  In many ways it tells us more about the reality of situations than more naturalistic works but in the case of Starred Up the drama is so involving, thanks mainly to the strong performances by Ben Mendelsohn and Jack O’Connell, that when the generic prison movie elements do surface they disrupt rather than drive proceedings.  But there is still plenty to like here because the central thrust of the movie shines through bringing moments of progress that feel like surfacing for air and a constrained tender note that is perfectly realised.