Discussion of Characters in LotR

In my opinion, Denethor was almost totally ruined. In the book, he was intelligent, he had a reason for his opinions, he was a very strong character. There was a wonderful tension between him and Gandalf because they were both very stubborn, and both thought they knew better what course to take. In the movie, Denethor is an arrogant fool from the start. Instead of going mad with the death or his only remaining son, he is mad all along. I'm disappointed.