There are many ways to categorize the movies. I sometimes divide movies into two: one which builds up the story & tension dynamically and another which focuses on characters' emotion at certain event and gives message. If the director succeeds in either one of the two, he or she can make a fabulous movie. If the director grasps both aspects, the movie achieves the level of masterpiece.
'Voice of Silence' is mediocre because the story is never fully developed and it is hard to figure out what the movie is trying to say. Interesting topic that a guy who digs up the dead body happens to be a kidnapper. It is a good start. However, the whole movie is at sea, floating around, never diving deep in the water. It seems like the director wants to highlight characters' emotions and breaks traditional storyline. However, without solid storyline, this inventive try of breaking the stereotype is no use. It looks rather pretentious and empty.
Some scenes are out of line. People killing the victim and all the blood.. well it's permissible in the movie. However, killing a person in front of a kid, carrying the dead body in front of her, AND she being okay with it such as helping a guy picking up the blood-stained tissue and as drawing a flower out of dead person's blood is beyond horror, almost inhumane. Very disturbing and distorted directing.