Unfortunately, the original book was far, far better.
The protagonist went to a little village on a small island in the Sicily area - IIRC - to recover. He spent his time working with the locals, drying himself out, regaining his physical stamina and skills, and getting a handle on what he wanted to do.
The main problem I had with this film was threefold:
1. Denzel Washington, an otherwise outstanding actor, does not do sheer rage or contained fury well at all. His best "menacing glare" is hardly different from his introspective look. He is better at other kinds of films.
2. Denzel Washington is black. The only reason this matters is that it would be almost impossible for a black man to "blend in" with and hide amongst an Italian population. But in the original book, the guy is white and can pass for Italian, and has learned the language and the dialect. He does blend in, and can move efficiently through the people around him without sticking out like a sore thumb. Chalk this one up to Hollywood and its Oscar fixation.
3. I dislike changing endings as a general rule. The original protagonist did not die, nor did the little girl live. The fact that the little girl - in the book - was both sexually molested and then brutally murdered is, in fact, what fuels his all-consuming rage and need for revenge. It is what literally sets him "on fire", and drives him to any lengths, no matter how brutal, to bring revenge and retribution to the kidnappers and anyoner else involved. For once in his life, he finally had feelings again about someone, and he is determined to bring pain and suffering and death to any responsible for taking it away from him and leaving him in his emotional limbo again. Without that clear motivation, the remaining movie version is badly weakened.
Washington, to me, is not so much an action star as a very human kind of guy who does better in films that display that side of him. Some actors are like that, and it is a shame that Hollywood forces them to "cross the line" into acting areas in which they are not as comfortable or as capable. If the black guy had been Wesley Snipes, for example, the problems with the movie would have remained, but the rage would have been there for all to see. That venerable old-timer, Sidney Poitier, did contained rage very well indeed.
The old-timer white actors, all gone now, would have done it even better. They came from a different lineage, before all the touchy-feely stuff, when America worshipped tough-guy bad-ass actors. The "white" thing, BTW, just goes back to blending in with a bunch of Italians. Pacino, for instance, would have portrayed the protagonist superbly and believably.
Ah, well...this is the same Hollywood that always used white men as American Indians and cast the immortal John Wayne as Ghengis Khan. the Fench said it all:
"The more things change, the more they stay the same."