An innocent man goes to jail being charged for beating some old woman (with deathly result). He's got no alibi and the only witness of the incident recognize him and die few days later (very old woman). Now he's trying to live in the new environment.
Will it change him? How can he handle that? What side of prisoners he'll choose (git-men or mug)?
You must see it yourself.
In my opinion: That movie shows polish prison in excellent way. And the young actor should get a medal for playing. You'll got few minutes for thinking 'bout your innocence.