Werner Herzog’s take on death row is one of my festival top three. It’s done in his own unique style and although it’s clear he opposes the system, you get to see all sides of the argument from the prisoners to the families of the victims to the executioner. Herzog, a bit like Nick Broomfield, has the knack of getting his subjects to really open up to him in a short space of time, whether it’s the slightly bumbling sounding questioning or some sort of documentary making magic powder, whatever it is, it works. ‘Please describe an encounter with a squirrel’ for example, leads to some of the most moving testimony from the death row chaplain. There is plenty to chew on here, although the grim facts of the case – that three people were murdered because two not very intelligent young men wanted their cars – are hard to argue with and Herzog doesn’t shy away from showing the brutal reality of the crimes.

Apparently Herzog’s initial plan was to focus on a few different inmates, but having stumbled on Michael Perry he obviously decided there was more than enough material in his story. And indeed there is. Perry was convicted of three homicides with his friend Jason Burkett. Burkett’s father, a lifelong jail inhabitee himself, made an impassioned speech in court and managed to save Jason from death row but Perry wasn’t so lucky and we meet him a week before his execution date. He’s a childlike and not particularly likeable man who has never admitted his guilt and whose conversion to christianity seems to have expunged any fear of death. It’s a shame we don’t hear more from him, although whether there is any more depth to him than Herzog finds through the glass wall in the prison is debateable.

Everyone in the film has a remarkable and terrible story – one woman’s list of the dreadful things that had befallen her nearest and dearest in the space of a few years was so unrelenting it sent a ripple of laughter round the audience. And the revelation towards the end of the film that Burkett has fathered a child from within prison raises all sorts of questions about smuggling and turkey basters that thankfully we don’t get too much information on.

Herzog has found himself in the centre of a whirlwind of crime and tragedy which only abates when we meet the man whose job it was to oversee the executions. To him, it was a day job which he took pride in doing well until, after he executed his first female prisoner (and 125th in total), he had a breakdown and quit his job immediately – now he’s a very vocal opponent of the death penalty. It’s pretty clear from the stories here that it doesn’t exactly act as a deterrent.

There’s so much to think about here, and it’s dealt with in a style that sometimes makes you want to look away and sometimes makes you laugh – it’s hard not to see the justice system here as anything but barbaric, but Herzog lets his subjects tell you that, even though sometimes they don’t realise they are saying it.