The basic story is the same as the book but they have done quite a lot of changes…and a lot of them aren't good. In the beginning they have added to the story by letting Ben finding Father Callahan and going after him. I won't spoil it for you by revealing what happens but…it's very wrong!
The other issues they have changed in part 1 are small but oh so important for the plot. They have turned the shy and somewhat lonely boy Mark into somewhat of a bully, totally wrong. The romantic and funny scene where Ben and Susan meat in the part is gone. It's the scene where she is reading his book and he jokes about how she treats the book. As with Mark they have also changed the personality of Straker. In the book he is rather sophisticated and laid back, here he is more cocky and blunt.
One change that they have done to the basic plot is that Ben has much bigger problems in this version. I guess that it's not a big problem but I don't see why they would change it. I mean it doesn't really change the reason he is there, it's just bigger without interfering with the story…and this is the worst kind of changes. Changes that are done for no particular reason other then they feel they want to do it different or whatever. Not a smart move when you're dealing with King fans.
How about the actors and accesses then? Well, some are good, some are bad and one is perfect. One of the good ones is Rob Lowe who is doing a good job portraying the hunted Ben Mears. And, after all, it's not his fault that they have screwed up his characters background. Donald Sutherland and Rutger Hauer do their best but unfortunately they don't reach all the way. Sutherland as Straker is just too much and Hauer as Barlow is just too little.
The perfect one is James Crowell as Father Callahan. If they ever do a movie version of The Dark Tower I hope they will bring him back as Callahan. He is just as I imagined him when I read Wolves of the Calla.
Unfortunately to many of the actors and actresses are too young. Andre Braugher, Samantha Mathis and most of the co-stars are way to young if you ask me. The movie itself looks very fresh and that is a good thing but it seams that they wanted to make the characters fresh as well. Unfortunately it doesn't work. These characters in the book aren't all young and good looking…
Oh and then they go ahead and let Sandy's husband blackmail Dr. Cody. It's a really, really bad change that robs us from one of the strongest scenes from the book (and the original miniseries). Yes, you got it, the-shotgun-in-the-mouth-scene.
Part 2 is better then part 1. More happens and we get to see all the vampires. The FX is well done. What's not so good is that now the vampires are smart. In the book they are more like zombies but here they are the same as before they become vampires, the just have longer teeth… Two scenes show this failure in screenwriting extra well. One is where Mike Ryerson visits Matt Burke and they start talking to each other about Mike's scars? What is that all about? The other scene is when Ben is talking to Susan and she tries to convince him that it's so much better to be a vampire then a living being. These two scenes are perfect examples of how a script should not be written!
Unfortunately Ben's past is revealed in it's full as well. I say unfortunately because as I said earlier, here they have made changes that don't interfere with the story in any way and they could have used the one from the book without any problems.
The ending is quite a bit different as well from the book and personally I can't see why they would make that change… It's not bad but why not follow the book it's supposed to be based on?