This is by far the worst film adaptation of a book (series) that I have ever seen. Two of the four main characters were cut completely, the plot was hacked to pieces, the dialogue was terrible, and it in no way resembles the books outside of the name.
Putting that aside and looking at it as its own thing, it is still terrible. Cliche after cliche. Halfway decent CGI surrounded by nearly disgusting dialogue. I don't know what possessed the studio to destroy a King novel in such a way, but they could have at least made a decent movie and didn't.