This Netflix documentary is terrifying, beautiful and bang up to date. Set against the homely backdrop of the American Midwest, filmmakers Laura Ricciardi and Moira Demos have made the most compelling documentary in the world. Part One follows Steven Avery and Brendan Dassey from Manitowoc County, Wisconsin as they are tried for the rape and murder of a woman, while their families weep for them at home. It caused international outrage and a swelling of support for the two men, who faced what looked like serious abuse of power by the police and prosecution services in Manitowoc. If you haven’t seen Part One, watch it, but if you have, then you’re in for an amazing sequel in Part Two.

A new hero enters the fray in the devastating shape of Steven’s new lawyer Kathleen Zellner. Zellner has a track record of overturning wrongful convictions, and she’s convinced Steven Avery and Brendan Dassey are innocent. If you didn’t think so at the end of series one, then you will definitely think so at the end of series two. Zellner says that neither the police nor prosecution ever investigated the murder of victim Theresa Halbach, but that she will.

She goes on to destroy the prosecution’s shoddy case with a series of practical forensic experiments and expert testimony. She also puts forward credible theories on who the murderer(s) of Theresa might be. She outright states Avery was framed and that the prosecution was corrupt. In fact the police had a very strong motive to get Avery out of the way, considering he was suing them at the time of his arrest for $36 million.

There is surprising resistance from many quarters to finding the real killers, but you can understand why the state of Wisconsin doesn’t want the case re-opened. They are scared of shining a light on the behaviour of the police and prosecution services. But, if there is a good case against Steven Avery, they should be willing to present it again, in the light of new evidence, although as Kathleen Zellner says, they wouldn’t get a conviction again.

Part of the concern over the convictions, was how the story of what was supposed to have happened to Theresa Halbach actually all came from a coerced (and recanted) confession from Avery’s 16 year old nephew Brendan Dassey, who has learning difficulties. Brendan was interrogated alone by agents who fed him the story they wanted to hear back, and Brendan hopelessly obeyed them. It’s an infamous, almost certainly unconstitutional, interrogation and would have been thrown out by any sensible judge. Making a Murderer part 2 also focuses on the attempts by Brendan’s lawyers to get the confession recognised for what it is, and they face a constant battle against a legal system that doesn’t want to know.

In the meantime, on the Avery case, Zellner is uncovering new evidence all the time. Some of the many things uncovered in the series are that the Manitowoc coroner was illegally ordered by the police to stay away from the alleged crime scene, that the DNA evidence used in the trial doesn’t seem to come from the right sources (saliva where it should have been skull and blood) or appears in implausible patterns according to blood spatter experts. There’s also a key witness who saw (and reported) Theresa Halbach’s abandoned car in a different location than Avery’s property, which suggests it was moved after the murder to implicate him. Much of the prosecution case is debunked by the knockout Zellner, who likens saving innocent people falsely imprisoned to saving men trapped underground in a collapsed mine. She’s just not going to give up on them.