The Heart Is a Lonely Hunter (1968)

... and from this man who could not speak or hear, the girl heard many things.

Singer is a deaf-mute whose small world brings him in contact with a young girl, Mick, who cherishes a seemingly hopeless dream of becoming a concert pianist. At first hostile, Mick soon becomes friends with Singer, hoping to enlarge his small world. Three other central characters come to Singer for help also, each of them seeing in him a powerful force.