According to the information on the website for this movie and in the trailer embedded below, two friends from the past reconnect and go fishing. They are worlds apart in their approach and goals to fly fishing. One fishes to catch and is very much into that aspect, while the other strives to achieve the perfect cast and catching is meaningless.
It’s an interesting portrayal and a concept that is dividing the outdoor sports community in many other ways besides fishing.
I haven’t seen the entire movie.