"They kill with their love", says John Coffey, pointing out that it happens every day, all over the world. The Green Mile is a film about many diverse topics, but fundamentally it is about the harm humans inflict on other members of their own species.
The Green Mile is a term referring to the death row in the Louisiana State Penintiary. Here, the prisoners who are to be executed are held until it is their time, and then they walk on a green floor to the electric chair (ergo, the title). The movie is told as a flashback from the perspective of Paul Edgecomb (Tom Hanks) who is in charge of the death row inmates. His job is to ensure that the prisoners are executed peacefully (whatever that means) since people facing their imminent death can get agitated. To this end, even though the people he's dealing with have been convicted of horrific crimes, he treats them with dignity and respect. Aiding him are Brutus Howell (David Morse), Dean Stanton (Barry Pepper) and Harry Terwilleger (Jeffrey DeMunn). In addition, there is Percy Wetmore (Doug Hutchison), a newly-appointed guard whose sole reason for being there is to satisfy his sadistic pleasure of watching someone be put to death on the electric chair.
The movie picks up pace when a new inmate, Coffey (Michael Clarke Duncan), is brought in for the murder of two young white girls. Coffey, a black and lumbering giant, is not clearly aware of his circumstance, and even though he is innocent there is little chance that anyone would believe him. But Edgecomb soon discovers that Coffey has special healing powers and they forge a strong bond. A lot of the movie is spent exploring the positive bond between Edgecomb and Coffey, contrasted to the negativity that Percy brings to the proceedings (with horrific consequences).
Like I said, the movie touches upon many topics, and each of them is worthy of comment. It illustrates the true nature of the death penalty, showing how cruel and barbaric it is as well as showing how innocent people can easily be put in positions where they are executed unjustly. The movie also touches upon the issue of Judeo-Christian faith and god, and as an atheist, I found it the least interesting topic (it's also not sufficiently explored except to illustrate that god wouldn't have given powers like the kind Coffey has if Coffey truly was destined to be a child killer). The movie is about compassion---Coffey is a Christ-like figure who dies for humanity's sins, crucified by people who don't know better. Yet he himself is not capable of complete forgiveness (unlike good old JC), and a key portion of the plot involves him getting his revenge (to the rousing cheers of the audience). But as I say above, ultimately what ties all of this together is that everyone seeks to harm someone else, whether justified or not. The parents of the children Coffey is believed to have killed have venom in their minds against him. Percy and a maniacal prison inmate (Sam Rockwell) seek nothing more than perverse destruction. Even the prison guards really have one sole purpose: to help kill. Coffey appears to be the only one who truly seeks to heal, but that is not without exception either and in the end, he too kills with his love.
The film is powerful and emotive, thanks to brilliant performances by a great cast. Hanks is solid as ever, but the real credit for the film must go to Duncan, who is able to deliver a preachy message without proselytising too much. When Duncan talks about the harm humanity inflicts on one other, with tears rolling down his cheek, it is an extremely poignant and telling moment. The ending bit (where Edgecomb tells about living too long) was unnecessary I thought and detracted from an otherwise perfect film. When Edgecomb talks about the same sorts of issues Duncan talks about, it doesn't come off as sincere and heart-felt. Hutchinson and Rockwell portray the least-likeable characters in the film and they pull it off well.
I've read almost all of Stephen King's books and this is a movie that captures in spirit his profound story-telling style (in general). King's stories mix idealism and cynicism well (mostly leaning towards the latter), using the supernatural as a plot device. They present a rather bleak world view because of their exploration of human darkness. While the film does end up portraying a sanitised view of King's vision, underneath the surface lies the depiction of how depraved we "civilised" beings can behave.