In this period drama spanning 1946 to 1967, Andy Dufresne (Tim Robbins), a soft-spoken, respected Maine banker, is convicted of the murders of his unfaithful wife and her lover. He receives a double-life sentence and is shipped off to Shawshank State Prison, Maine's toughest maximum security penitentiary. Despised at first by the other inmates because of his introverted manner, he slowly forges an unlikely friendship with the prison "fixer" Red (Morgan Freeman,) and his gang. Red is a useful man to know as he runs a nice little sideline in procuring cigarettes, brandy, in fact anything for a price.
Robbins only wants a poster of Rita Hayworth and a mini geology hammer to pursue his love of stone carving. However, in prison life he has to deal with rape, beatings and a sadistic regime that serves only to break the inmates with no concern for humanity or justice. Despite this, Robbins determines to survive on his accountancy wits. Initially promising to help out a warder with his inheritance tax if the work gang he is on is given a bottle of beer apiece, Robbins gradually comes to a position of power in the prison as the accountant for corrupt prison warden Sammuel Norton's (Bob Gunton) illegal money-making schemes.
Throughout their time in prison, both men hold out hopes for parole. However, because Dufresne is so useful to Norton and because the parole board will not believe that Red is sufficiently penitent for his crimes, neither man is seriously considered by the parole board and they forge a strong friendship based on mutual, quiet respect.
Red concentrates on his role of "fixer" while Dufresne uses his position with the governor to establish a prison library in which he concentrates on educating the younger prisoners. When one of those prisoners joins the class and claims that he can prove Dufresne's innocence, there is hope that he will be allowed to appeal to the courts to gain his freedom. Norton will have none of it though, and Dufresne determines to gain a momentous revenge on the sadistic warden.