I remember seeing Nunzio on WHT (Wometco Home Theater) which was a pay TV service that pre-dated cable. The film left such an impression on me that I haven't forgotten it to this day.
I won't go into the plot as it's been covered here but David Proval's performance as a mentally challenged delivery boy is heartbreaking and pitch perfect.
His brother, played by the excellent James Andronica (who also wrote the script), loves Nunzio and protects him, as any big brother should.
While the script may be formulaic, it works.
David Proval and James Andronica are clearly committed here and the way they captured the lives of these characters was terrific. It feels very genuine and authentic as NYC is practically a character in and of itself.
If you can see this film (there are a few websites streaming an old WHT version, but the quality is poor), check it out, you won't regret it.
The fact that this movie hasn't been released on DVD/Blu-ray is very sad.
