More or less as a challenge, Stephen King published this story as a serial in six parts. Just as in Charles Dickens's time, the story was crafted while the book is already in production. In keeping with the serial concept, the first edition consists of six thin cheap paperbacks sold in various stores.
The main characters are three people on death row and their warders. The book has a clear narrative voice belonging to Paul Edgecombe, one of the warders. The basic plot concerns Paul Edgecombe and a few prisoners and coworkers in a prison ward. "The green mile" is the stretch from the cells where the prisoners live to the execution room beyond Edgecombe's office. The story takes place in the 1930s, but there is also a framing plot where Paul is an old man in a nursing home, trying to exorcise the ghosts of his past by writing.
The three prisoners all come to the prison at about the same time. The one that the store centers aroung is John Coffey, a gigantic negro who is convicted of raping and killing two small girls. He is noticed, partly because of his size, but also for his strange behaviour. He seems barely intelligent enough to be able to eat by himself, but in spite of that he's supposed to have lured the girls away from their home while eluding the watchdog. He's also one of the calmest and mildest prisoners the warders have ever seen. The other two prisoners are more like one expects them to be. One of them--Delacroix--is small and cowardly, the other--Willy Wharton--is tough and boasting, claiming to be a modern Billy the kid.
The story also features a small an unnaturally intelligent mouse who befriends Delacroix; the mouse learns various tricks and appears to follow commands, and Delacroix insists that the mouse whispers secrets about the other people in his ear.
Over time, the warders realize that there is something special with John Coffey. In spite of his lack of intelligence he has some special power.
Sometimes it seems that the physical format imposed on the story with 90 pages per part (a little more in the last part) has forced King to pad the story a bit here and there to have enough pages in each part and still get a cliffhanger at the end of each part.
After its first publication, The Green Mile has been published in one volume. The first edition contains a bit where the narrator speaks directly to the reader; the republished work contains an additional foreword. The novel was left basically untouched but King did change one part where a character in a straightjacket wipes his brow (a mistake that slipped past both him and his editor the first time around).