The movie is like a Deja Vu of films such as Erin Brockovich and so it depends largely on the performance of its lead character; in this case Mark Ruffalo. The storyline is known to anyone who has access to Google. The script is pretty average and so is the direction.
What stands out is Mark's performance.
I continue to firmly believe that he is one of the most underrated actors of our times.
Review of Dark Waters
