Escape films are those which,
involve the audience in the plight of either a wrongly accused man or an attractive criminal (and) some of them, managed to combine an escape plot with bigger statements about human nature and freedom. (AllMovie.com)
The Shawshank Redemption leads us through the experience of Andy Dufresne who is accused of killing his wife and her lover. Although he denies the crime, all the evidence points to him and he is thrown in the Shawshank State Prison. One of his inmates, years later, reveals that Dufresne is indeed innocent and the real killer is still alive.
When the warden doesn't allow him to have his case re-opened, Dufresne executes his escape. As his escape is shown we see that he has been working on it for the past nineteen years. This plan he'd been developing is what kept him sane, as he said to Morgan Freeman, "Fear can hold you prisoner. Hope can set you free." (The Shawshank Redemption). Though Dufresne is speaking of being a prisoner, he also is making a larger statement about human nature and what he has learned while in the Shawshank.
A prison film is,
A subgenre of the crime film that centers on the difficult living...