I was so happy to see that Malcolm Lowry's Under the Volcano was being aired this week on TNT so that I 
could once again see the masterful performance of Albert Finney who plays the alcoholic British consol Geoffrey Firmin who lives in Cuernavaca, Mexico in 1938. The entire book/movie covers one day in the life of Geoffrey Firmin, his last day. Coincidentally, this day is the Mexican celebration called the Day of the Dead. Under the Volcano was one of the most difficult and enigmatic books that I had ever read. This means that it was almost an impossible task to create a movie out of such a book. Nonetheless, John Huston did a creditable job of portraying the man, Geoffrey Firmin, even though it in no way covers this multilevel book. I agree with an IMDB reviewer that to do justice to Lowry's book would have required a "12-part miniseries." The same reviewer states the following:
"That's the difference between the novel and the film: though no fault of the director or writer (16 different film treatments were attempted before this version) the movie simply scratches the surface: it's merely about a drunkard unable to forgive his wife--who cheated on him with his half-brother--returning to him on the auspicious Day of Dead fiesta in Mexico; while in the novel, with its complex back-stories the three main characters--Firmin, his wife Yvonne and half-brother Hugh--are bound together by worldly and inexplicable spiritual forces, and we get an insight as to why they can't tear away from the train-wreck that is Geoffrey Firmin, while retaining the sorry universal aspect of the main character (Firmin) as God's Man itself."
I highly recommend this movie. You will be thinking about it for a long time after your viewing.