In their wisdom, screenwriters Darren Aronofsky and Ari Handel set out not so much to distort this story but to re-write it. They dispense with the notion that sons Ham and Japeth had wives and replace them on the ark with an evil descendant-king of Cain, so that evil finds its way onto the ark. This allows for an epic battle to the death between Noah and the evil descendant-king towards the film's climax. Noah is portrayed not as a good man but as a warrior, a mass-murderer and as a cruel and ruthless man intent on committing murder in the name of "the Creator". The result is a poor man's "Gladiator on Water".
Given that "the Creator" wants to preserve "good" on the ark, it is a strange twist of fate that Methuselah (Anthony Hopkins), for all intents and purposes a better man than Noah, is not allowed onto the ark but rather perishes in a violent storm along with all the "evil" men. Obviously his goodness is not required for the final epic battle.
The interpretation of "good" is quite a muddle for most of the movie. Noah and his middle son Ham have many shortcomings when it comes to being "good" men. Noah is willing to kill innocent people - as well as a multitude of "bad" people - while Ham is beset by jealousy and revenge to the point of willing to become an accomplice to murder. I found it difficult to feel compassion for either.
The movie also included the introduction of rock monsters who come to Noah's aid, taking the movie squarely into the horror genre. Perhaps fantasy is a better word, because even though they start off as potentially threatening creatures, they eventually come to Noah's aid - and even end up killing most of the film's population before the flood can destroy them.
I watched the entire movie in the mistaken belief that things would improve as it went along. They didn't - and at the end I was left with the feeling that I was glad that I waited until the movie had come to TV because I would have felt cheated paying to see it at a cinema.