Transformation is central to both Patrick Suskind's novel Perfume: The Story of a Murderer and the film The Green Mile. Let's look at the kinds of transformations that help present these works' ideas.
In the novel, transformation is quite subtle. Grenouille, after all, does not really change all that much throughout the course of the story. His enhanced sense of smell remains the same, as does his sense of self-grandeur. Yet we might notice that Grenouille's ideas about dominating others change by the end of the book. Grenouille has had the goal of using his talents to increase his own power. When he finally captures the scent of beauty, he thinks that all of his dreams will come true. He will rule the world. Yet he quickly discovers that there is actually little satisfaction in ruling over others, for they do not understand him and do not appreciate his power. They simply do not care, and Grenouille decides to commit suicide.
In the film, transformation is much more evident. Think about Paul, for instance. His whole outlook on life is changed by his encounter with John. He learns to see the world in a different way. Percy, on the other hand, experiences a much more negative transformation as he goes insane as a consequence of his extreme cruelty and John's power. Basically, most people who encounter John Coffey are changed in some way, for the good or for the bad depending on their characters.