The Lord of the Rings is by far one of the biggest achievements in film history. Peter Jackson's adaptation of the three books written by J.R.R. Tolkien have won a ton of awards and was highly regarded by critics. Though the Lord of the Rings trilogy was in trouble from the beginning. Viggo Mortensen was not the original actor cast to play the once and future king of Gondor. But luckily when he was eventually brought in, it was proven that the Lord of the Rings would not have been the same movie without him.