Like any other slice-of-life anime, the plot is relatively simple, however there is an outstanding attention to the development of the characters.
As usual for Naoko Yamada, most of the scenes and dialogue from the manga are present, however she adds so much more to the anime, making it a truly emotional experience.
The story is very mature, not in the sense that it is dark and gritty, but more in the sense that the characters are fully realised, presented in a realistic manner.
A Silent Voice forgoes anime archetypes by maintaining internal-consistency in all of its characters, making all of their actions relatable, or at least understandable.
It is difficult to describe why the audio-visuals work so well using just words.
I found the film to be a powerful, transformative experience.