Chicago. A man has been innocently imprisoned - for more than twenty years. All claims have been rejected. He is condemned to life sentence. His only chance: a handful of law students.

At the Northwestern University of Chicago, several groups of students are working on cases that even top American lawyers don't dare to tackle: cases of innocence without DNA proof. Legal exercises with real peoples' lives: there is no evidence of the guilt of the people they look after - but no evidence of their innocence either - only the prisoners' own statement. The students take the chance to be part of a group of prospective lawyers at the exciting search for clues in the gangland of Chicago.

In search of proof of the innocence of the prisoners the undergraduates encounter shady witnesses, corrupt and violent police officers and not very credible experts. The search is frustrating and dangerous. And still, sometimes the young people manage to free the detainees that they have taken on - but not always.

The film tells the story of a prisoner and his sideline heroes for a semester - students at the Northwestern University in Chicago - in documentary form, partly recorded by the students themselves.