Maclean said that in his talk he’s decided to fling caution aside and tell the truth. In part, that means naming the people he thinks are standing in the way of protecting the Blackfoot. He said that, though the resonance of his father’s work and its subsequent film adaptation have strained the waterway, the two forces have also helped spur efforts to improve the health of the river, which at one point was so polluted that the younger Maclean refused to fish there.